diff --git a/packages/language-server/package.json b/packages/language-server/package.json
index 1b872a3c2..c15475304 100644
--- a/packages/language-server/package.json
+++ b/packages/language-server/package.json
@@ -63,7 +63,7 @@
         "vscode-css-languageservice": "5.0.0",
         "vscode-emmet-helper": "2.1.2",
         "vscode-html-languageservice": "4.0.0",
-        "vscode-languageserver": "7.0.0",
+        "vscode-languageserver": "7.1.0-next.4",
         "vscode-languageserver-types": "3.16.0",
         "vscode-uri": "2.1.2"
     }
diff --git a/packages/language-server/src/plugins/PluginHost.ts b/packages/language-server/src/plugins/PluginHost.ts
index c32c47228..54fbb29fd 100644
--- a/packages/language-server/src/plugins/PluginHost.ts
+++ b/packages/language-server/src/plugins/PluginHost.ts
@@ -1,5 +1,6 @@
 import { flatten } from 'lodash';
 import {
+    CancellationToken,
     CodeAction,
     CodeActionContext,
     Color,
@@ -86,7 +87,8 @@ export class PluginHost implements LSProvider, OnWatchFileChanges {
     async getCompletions(
         textDocument: TextDocumentIdentifier,
         position: Position,
-        completionContext?: CompletionContext
+        completionContext?: CompletionContext,
+        cancellationToken?: CancellationToken
     ): Promise<CompletionList> {
         const document = this.getDocument(textDocument.uri);
         if (!document) {
@@ -96,7 +98,7 @@ export class PluginHost implements LSProvider, OnWatchFileChanges {
         const completions = (
             await this.execute<CompletionList>(
                 'getCompletions',
-                [document, position, completionContext],
+                [document, position, completionContext, cancellationToken],
                 ExecuteMode.Collect
             )
         ).filter((completion) => completion != null);
@@ -127,7 +129,8 @@ export class PluginHost implements LSProvider, OnWatchFileChanges {
 
     async resolveCompletion(
         textDocument: TextDocumentIdentifier,
-        completionItem: AppCompletionItem
+        completionItem: AppCompletionItem,
+        cancellationToken: CancellationToken
     ): Promise<CompletionItem> {
         const document = this.getDocument(textDocument.uri);
 
@@ -137,7 +140,7 @@ export class PluginHost implements LSProvider, OnWatchFileChanges {
 
         const result = await this.execute<CompletionItem>(
             'resolveCompletion',
-            [document, completionItem],
+            [document, completionItem, cancellationToken],
             ExecuteMode.FirstNonNull
         );
 
@@ -212,7 +215,10 @@ export class PluginHost implements LSProvider, OnWatchFileChanges {
         );
     }
 
-    async getDocumentSymbols(textDocument: TextDocumentIdentifier): Promise<SymbolInformation[]> {
+    async getDocumentSymbols(
+        textDocument: TextDocumentIdentifier,
+        cancellationToken: CancellationToken
+    ): Promise<SymbolInformation[]> {
         const document = this.getDocument(textDocument.uri);
         if (!document) {
             throw new Error('Cannot call methods on an unopened document');
@@ -221,7 +227,7 @@ export class PluginHost implements LSProvider, OnWatchFileChanges {
         return flatten(
             await this.execute<SymbolInformation[]>(
                 'getDocumentSymbols',
-                [document],
+                [document, cancellationToken],
                 ExecuteMode.Collect
             )
         );
@@ -256,7 +262,8 @@ export class PluginHost implements LSProvider, OnWatchFileChanges {
     async getCodeActions(
         textDocument: TextDocumentIdentifier,
         range: Range,
-        context: CodeActionContext
+        context: CodeActionContext,
+        cancellationToken: CancellationToken
     ): Promise<CodeAction[]> {
         const document = this.getDocument(textDocument.uri);
         if (!document) {
@@ -266,7 +273,7 @@ export class PluginHost implements LSProvider, OnWatchFileChanges {
         return flatten(
             await this.execute<CodeAction[]>(
                 'getCodeActions',
-                [document, range, context],
+                [document, range, context, cancellationToken],
                 ExecuteMode.Collect
             )
         );
@@ -350,7 +357,8 @@ export class PluginHost implements LSProvider, OnWatchFileChanges {
     async getSignatureHelp(
         textDocument: TextDocumentIdentifier,
         position: Position,
-        context: SignatureHelpContext | undefined
+        context: SignatureHelpContext | undefined,
+        cancellationToken: CancellationToken
     ): Promise<SignatureHelp | null> {
         const document = this.getDocument(textDocument.uri);
         if (!document) {
@@ -359,7 +367,7 @@ export class PluginHost implements LSProvider, OnWatchFileChanges {
 
         return await this.execute<any>(
             'getSignatureHelp',
-            [document, position, context],
+            [document, position, context, cancellationToken],
             ExecuteMode.FirstNonNull
         );
     }
@@ -403,7 +411,11 @@ export class PluginHost implements LSProvider, OnWatchFileChanges {
         }
     }
 
-    async getSemanticTokens(textDocument: TextDocumentIdentifier, range?: Range) {
+    async getSemanticTokens(
+        textDocument: TextDocumentIdentifier,
+        range?: Range,
+        cancellationToken?: CancellationToken
+    ) {
         const document = this.getDocument(textDocument.uri);
         if (!document) {
             throw new Error('Cannot call methods on an unopened document');
@@ -411,7 +423,7 @@ export class PluginHost implements LSProvider, OnWatchFileChanges {
 
         return await this.execute<SemanticTokens>(
             'getSemanticTokens',
-            [document, range],
+            [document, range, cancellationToken],
             ExecuteMode.FirstNonNull
         );
     }
diff --git a/packages/language-server/src/plugins/interfaces.ts b/packages/language-server/src/plugins/interfaces.ts
index a4d1122c5..5f6f9ac09 100644
--- a/packages/language-server/src/plugins/interfaces.ts
+++ b/packages/language-server/src/plugins/interfaces.ts
@@ -1,4 +1,5 @@
 import {
+    CancellationToken,
     CompletionContext,
     FileChangeType,
     LinkedEditingRanges,
@@ -53,12 +54,14 @@ export interface CompletionsProvider<T extends TextDocumentIdentifier = any> {
     getCompletions(
         document: Document,
         position: Position,
-        completionContext?: CompletionContext
+        completionContext?: CompletionContext,
+        cancellationToken?: CancellationToken
     ): Resolvable<AppCompletionList<T> | null>;
 
     resolveCompletion?(
         document: Document,
-        completionItem: AppCompletionItem<T>
+        completionItem: AppCompletionItem<T>,
+        cancellationToken?: CancellationToken
     ): Resolvable<AppCompletionItem<T>>;
 }
 
@@ -83,7 +86,10 @@ export interface ColorPresentationsProvider {
 }
 
 export interface DocumentSymbolsProvider {
-    getDocumentSymbols(document: Document): Resolvable<SymbolInformation[]>;
+    getDocumentSymbols(
+        document: Document,
+        cancellationToken?: CancellationToken
+    ): Resolvable<SymbolInformation[]>;
 }
 
 export interface DefinitionsProvider {
@@ -101,7 +107,8 @@ export interface CodeActionsProvider {
     getCodeActions(
         document: Document,
         range: Range,
-        context: CodeActionContext
+        context: CodeActionContext,
+        cancellationToken?: CancellationToken
     ): Resolvable<CodeAction[]>;
     executeCommand?(
         document: Document,
@@ -140,7 +147,8 @@ export interface SignatureHelpProvider {
     getSignatureHelp(
         document: Document,
         position: Position,
-        context: SignatureHelpContext | undefined
+        context: SignatureHelpContext | undefined,
+        cancellationToken?: CancellationToken
     ): Resolvable<SignatureHelp | null>;
 }
 
diff --git a/packages/language-server/src/plugins/svelte/SveltePlugin.ts b/packages/language-server/src/plugins/svelte/SveltePlugin.ts
index 7901fb025..88ded0cc9 100644
--- a/packages/language-server/src/plugins/svelte/SveltePlugin.ts
+++ b/packages/language-server/src/plugins/svelte/SveltePlugin.ts
@@ -9,7 +9,9 @@ import {
     Range,
     TextEdit,
     WorkspaceEdit,
-    SelectionRange
+    SelectionRange,
+    CancellationToken,
+    CompletionContext
 } from 'vscode-languageserver';
 import { Document } from '../../lib/documents';
 import { LSConfigManager, LSSvelteConfig } from '../../ls-config';
@@ -138,12 +140,22 @@ export class SveltePlugin
         }
     }
 
-    async getCompletions(document: Document, position: Position): Promise<CompletionList | null> {
+    async getCompletions(
+        document: Document,
+        position: Position,
+        _?: CompletionContext,
+        cancellationToken?: CancellationToken
+    ): Promise<CompletionList | null> {
         if (!this.featureEnabled('completions')) {
             return null;
         }
 
-        return getCompletions(await this.getSvelteDoc(document), position);
+        const svelteDoc = await this.getSvelteDoc(document);
+        if (cancellationToken?.isCancellationRequested) {
+            return null;
+        }
+
+        return getCompletions(svelteDoc, position);
     }
 
     async doHover(document: Document, position: Position): Promise<Hover | null> {
@@ -157,13 +169,19 @@ export class SveltePlugin
     async getCodeActions(
         document: Document,
         range: Range,
-        context: CodeActionContext
+        context: CodeActionContext,
+        cancellationToken?: CancellationToken
     ): Promise<CodeAction[]> {
         if (!this.featureEnabled('codeActions')) {
             return [];
         }
 
         const svelteDoc = await this.getSvelteDoc(document);
+
+        if (cancellationToken?.isCancellationRequested) {
+            return [];
+        }
+
         try {
             return getCodeActions(svelteDoc, range, context);
         } catch (error) {
diff --git a/packages/language-server/src/plugins/typescript/TypeScriptPlugin.ts b/packages/language-server/src/plugins/typescript/TypeScriptPlugin.ts
index c07a6553a..046628987 100644
--- a/packages/language-server/src/plugins/typescript/TypeScriptPlugin.ts
+++ b/packages/language-server/src/plugins/typescript/TypeScriptPlugin.ts
@@ -1,5 +1,6 @@
 import ts, { NavigationTree } from 'typescript';
 import {
+    CancellationToken,
     CodeAction,
     CodeActionContext,
     CompletionContext,
@@ -112,12 +113,15 @@ export class TypeScriptPlugin
         this.semanticTokensProvider = new SemanticTokensProviderImpl(this.lsAndTsDocResolver);
     }
 
-    async getDiagnostics(document: Document): Promise<Diagnostic[]> {
+    async getDiagnostics(
+        document: Document,
+        cancellationToken?: CancellationToken
+    ): Promise<Diagnostic[]> {
         if (!this.featureEnabled('diagnostics')) {
             return [];
         }
 
-        return this.diagnosticsProvider.getDiagnostics(document);
+        return this.diagnosticsProvider.getDiagnostics(document, cancellationToken);
     }
 
     async doHover(document: Document, position: Position): Promise<Hover | null> {
@@ -128,13 +132,21 @@ export class TypeScriptPlugin
         return this.hoverProvider.doHover(document, position);
     }
 
-    async getDocumentSymbols(document: Document): Promise<SymbolInformation[]> {
+    async getDocumentSymbols(
+        document: Document,
+        cancellationToken?: CancellationToken
+    ): Promise<SymbolInformation[]> {
         if (!this.featureEnabled('documentSymbols')) {
             return [];
         }
 
         const { lang, tsDoc } = await this.getLSAndTSDoc(document);
         const fragment = await tsDoc.getFragment();
+
+        if (cancellationToken?.isCancellationRequested) {
+            return [];
+        }
+
         const navTree = lang.getNavigationTree(tsDoc.filePath);
 
         const symbols: SymbolInformation[] = [];
@@ -209,7 +221,8 @@ export class TypeScriptPlugin
     async getCompletions(
         document: Document,
         position: Position,
-        completionContext?: CompletionContext
+        completionContext?: CompletionContext,
+        cancellationToken?: CancellationToken
     ): Promise<AppCompletionList<CompletionEntryWithIdentifer> | null> {
         if (!this.featureEnabled('completions')) {
             return null;
@@ -224,7 +237,8 @@ export class TypeScriptPlugin
         const completions = await this.completionProvider.getCompletions(
             document,
             position,
-            completionContext
+            completionContext,
+            cancellationToken
         );
 
         if (completions && tsDirectiveCommentCompletions) {
@@ -239,9 +253,14 @@ export class TypeScriptPlugin
 
     async resolveCompletion(
         document: Document,
-        completionItem: AppCompletionItem<CompletionEntryWithIdentifer>
+        completionItem: AppCompletionItem<CompletionEntryWithIdentifer>,
+        cancellationToken?: CancellationToken
     ): Promise<AppCompletionItem<CompletionEntryWithIdentifer>> {
-        return this.completionProvider.resolveCompletion(document, completionItem);
+        return this.completionProvider.resolveCompletion(
+            document,
+            completionItem,
+            cancellationToken
+        );
     }
 
     async getDefinitions(document: Document, position: Position): Promise<DefinitionLink[]> {
@@ -304,13 +323,14 @@ export class TypeScriptPlugin
     async getCodeActions(
         document: Document,
         range: Range,
-        context: CodeActionContext
+        context: CodeActionContext,
+        cancellationToken?: CancellationToken
     ): Promise<CodeAction[]> {
         if (!this.featureEnabled('codeActions')) {
             return [];
         }
 
-        return this.codeActionsProvider.getCodeActions(document, range, context);
+        return this.codeActionsProvider.getCodeActions(document, range, context, cancellationToken);
     }
 
     async executeCommand(
@@ -405,23 +425,37 @@ export class TypeScriptPlugin
     async getSignatureHelp(
         document: Document,
         position: Position,
-        context: SignatureHelpContext | undefined
+        context: SignatureHelpContext | undefined,
+        cancellationToken?: CancellationToken
     ): Promise<SignatureHelp | null> {
         if (!this.featureEnabled('signatureHelp')) {
             return null;
         }
 
-        return this.signatureHelpProvider.getSignatureHelp(document, position, context);
+        return this.signatureHelpProvider.getSignatureHelp(
+            document,
+            position,
+            context,
+            cancellationToken
+        );
     }
 
-    async getSemanticTokens(textDocument: Document, range?: Range): Promise<SemanticTokens | null> {
+    async getSemanticTokens(
+        textDocument: Document,
+        range?: Range,
+        cancellationToken?: CancellationToken
+    ): Promise<SemanticTokens | null> {
         if (!this.featureEnabled('semanticTokens')) {
             return {
                 data: []
             };
         }
 
-        return this.semanticTokensProvider.getSemanticTokens(textDocument, range);
+        return this.semanticTokensProvider.getSemanticTokens(
+            textDocument,
+            range,
+            cancellationToken
+        );
     }
 
     private async getLSAndTSDoc(document: Document) {
diff --git a/packages/language-server/src/plugins/typescript/features/CodeActionsProvider.ts b/packages/language-server/src/plugins/typescript/features/CodeActionsProvider.ts
index 9eb90ab20..1261bfd82 100644
--- a/packages/language-server/src/plugins/typescript/features/CodeActionsProvider.ts
+++ b/packages/language-server/src/plugins/typescript/features/CodeActionsProvider.ts
@@ -1,5 +1,6 @@
 import ts from 'typescript';
 import {
+    CancellationToken,
     CodeAction,
     CodeActionContext,
     CodeActionKind,
@@ -39,27 +40,31 @@ export class CodeActionsProviderImpl implements CodeActionsProvider {
     async getCodeActions(
         document: Document,
         range: Range,
-        context: CodeActionContext
+        context: CodeActionContext,
+        cancellationToken?: CancellationToken
     ): Promise<CodeAction[]> {
         if (context.only?.[0] === CodeActionKind.SourceOrganizeImports) {
-            return await this.organizeImports(document);
+            return await this.organizeImports(document, cancellationToken);
         }
 
         if (
             context.diagnostics.length &&
             (!context.only || context.only.includes(CodeActionKind.QuickFix))
         ) {
-            return await this.applyQuickfix(document, range, context);
+            return await this.applyQuickfix(document, range, context, cancellationToken);
         }
 
         if (!context.only || context.only.includes(CodeActionKind.Refactor)) {
-            return await this.getApplicableRefactors(document, range);
+            return await this.getApplicableRefactors(document, range, cancellationToken);
         }
 
         return [];
     }
 
-    private async organizeImports(document: Document): Promise<CodeAction[]> {
+    private async organizeImports(
+        document: Document,
+        cancellationToken: CancellationToken | undefined
+    ): Promise<CodeAction[]> {
         if (!document.scriptInfo && !document.moduleScriptInfo) {
             return [];
         }
@@ -67,6 +72,10 @@ export class CodeActionsProviderImpl implements CodeActionsProvider {
         const { lang, tsDoc, userPreferences } = await this.getLSAndTSDoc(document);
         const fragment = await tsDoc.getFragment();
 
+        if (cancellationToken?.isCancellationRequested) {
+            return [];
+        }
+
         const changes = lang.organizeImports(
             {
                 fileName: tsDoc.filePath,
@@ -149,10 +158,19 @@ export class CodeActionsProviderImpl implements CodeActionsProvider {
         return range;
     }
 
-    private async applyQuickfix(document: Document, range: Range, context: CodeActionContext) {
+    private async applyQuickfix(
+        document: Document,
+        range: Range,
+        context: CodeActionContext,
+        cancellationToken: CancellationToken | undefined
+    ) {
         const { lang, tsDoc, userPreferences } = await this.getLSAndTSDoc(document);
         const fragment = await tsDoc.getFragment();
 
+        if (cancellationToken?.isCancellationRequested) {
+            return [];
+        }
+
         const start = fragment.offsetAt(fragment.getGeneratedPosition(range.start));
         const end = fragment.offsetAt(fragment.getGeneratedPosition(range.end));
         const errorCodes: number[] = context.diagnostics.map((diag) => Number(diag.code));
@@ -257,7 +275,11 @@ export class CodeActionsProviderImpl implements CodeActionsProvider {
         );
     }
 
-    private async getApplicableRefactors(document: Document, range: Range): Promise<CodeAction[]> {
+    private async getApplicableRefactors(
+        document: Document,
+        range: Range,
+        cancellationToken: CancellationToken | undefined
+    ): Promise<CodeAction[]> {
         if (
             !isRangeInTag(range, document.scriptInfo) &&
             !isRangeInTag(range, document.moduleScriptInfo)
@@ -278,6 +300,11 @@ export class CodeActionsProviderImpl implements CodeActionsProvider {
 
         const { lang, tsDoc, userPreferences } = await this.getLSAndTSDoc(document);
         const fragment = await tsDoc.getFragment();
+
+        if (cancellationToken?.isCancellationRequested) {
+            return [];
+        }
+
         const textRange = {
             pos: fragment.offsetAt(fragment.getGeneratedPosition(range.start)),
             end: fragment.offsetAt(fragment.getGeneratedPosition(range.end))
diff --git a/packages/language-server/src/plugins/typescript/features/CompletionProvider.ts b/packages/language-server/src/plugins/typescript/features/CompletionProvider.ts
index c20a9cbe9..1e1cca834 100644
--- a/packages/language-server/src/plugins/typescript/features/CompletionProvider.ts
+++ b/packages/language-server/src/plugins/typescript/features/CompletionProvider.ts
@@ -1,5 +1,6 @@
 import ts from 'typescript';
 import {
+    CancellationToken,
     CompletionContext,
     CompletionList,
     CompletionTriggerKind,
@@ -68,7 +69,8 @@ export class CompletionsProviderImpl implements CompletionsProvider<CompletionEn
     async getCompletions(
         document: Document,
         position: Position,
-        completionContext?: CompletionContext
+        completionContext?: CompletionContext,
+        cancellationToken?: CancellationToken
     ): Promise<AppCompletionList<CompletionEntryWithIdentifer> | null> {
         if (isInTag(position, document.styleInfo)) {
             return null;
@@ -130,6 +132,10 @@ export class CompletionsProviderImpl implements CompletionsProvider<CompletionEn
             return getJsDocTemplateCompletion(fragment, lang, filePath, offset);
         }
 
+        if (cancellationToken?.isCancellationRequested) {
+            return null;
+        }
+
         const eventCompletions = await this.getEventCompletions(
             lang,
             document,
@@ -142,6 +148,10 @@ export class CompletionsProviderImpl implements CompletionsProvider<CompletionEn
             return CompletionList.create(eventCompletions, !!tsDoc.parserError);
         }
 
+        if (cancellationToken?.isCancellationRequested) {
+            return null;
+        }
+
         const completions =
             lang.getCompletionsAtPosition(filePath, offset, {
                 ...userPreferences,
@@ -318,7 +328,8 @@ export class CompletionsProviderImpl implements CompletionsProvider<CompletionEn
 
     async resolveCompletion(
         document: Document,
-        completionItem: AppCompletionItem<CompletionEntryWithIdentifer>
+        completionItem: AppCompletionItem<CompletionEntryWithIdentifer>,
+        cancellationToken?: CancellationToken
     ): Promise<AppCompletionItem<CompletionEntryWithIdentifer>> {
         const { data: comp } = completionItem;
         const { tsDoc, lang, userPreferences } = await this.lsAndTsDocResolver.getLSAndTSDoc(
@@ -327,11 +338,12 @@ export class CompletionsProviderImpl implements CompletionsProvider<CompletionEn
 
         const filePath = tsDoc.filePath;
 
-        if (!comp || !filePath) {
+        if (!comp || !filePath || cancellationToken?.isCancellationRequested) {
             return completionItem;
         }
 
         const fragment = await tsDoc.getFragment();
+
         const detail = lang.getCompletionEntryDetails(
             filePath,
             fragment.offsetAt(fragment.getGeneratedPosition(comp.position)),
diff --git a/packages/language-server/src/plugins/typescript/features/DiagnosticsProvider.ts b/packages/language-server/src/plugins/typescript/features/DiagnosticsProvider.ts
index 6873484cd..d2ae00de6 100644
--- a/packages/language-server/src/plugins/typescript/features/DiagnosticsProvider.ts
+++ b/packages/language-server/src/plugins/typescript/features/DiagnosticsProvider.ts
@@ -1,5 +1,5 @@
 import ts from 'typescript';
-import { Diagnostic, DiagnosticSeverity } from 'vscode-languageserver';
+import { CancellationToken, Diagnostic, DiagnosticSeverity } from 'vscode-languageserver';
 import {
     Document,
     mapObjWithRangeToOriginal,
@@ -15,10 +15,16 @@ import { isInGeneratedCode } from './utils';
 export class DiagnosticsProviderImpl implements DiagnosticsProvider {
     constructor(private readonly lsAndTsDocResolver: LSAndTSDocResolver) {}
 
-    async getDiagnostics(document: Document): Promise<Diagnostic[]> {
+    async getDiagnostics(
+        document: Document,
+        cancellationToken?: CancellationToken
+    ): Promise<Diagnostic[]> {
         const { lang, tsDoc } = await this.getLSAndTSDoc(document);
 
-        if (['coffee', 'coffeescript'].includes(document.getLanguageAttribute('script'))) {
+        if (
+            ['coffee', 'coffeescript'].includes(document.getLanguageAttribute('script')) ||
+            cancellationToken?.isCancellationRequested
+        ) {
             return [];
         }
 
diff --git a/packages/language-server/src/plugins/typescript/features/SemanticTokensProvider.ts b/packages/language-server/src/plugins/typescript/features/SemanticTokensProvider.ts
index d2e3e7061..34727d0a5 100644
--- a/packages/language-server/src/plugins/typescript/features/SemanticTokensProvider.ts
+++ b/packages/language-server/src/plugins/typescript/features/SemanticTokensProvider.ts
@@ -1,5 +1,10 @@
 import ts from 'typescript';
-import { Range, SemanticTokens, SemanticTokensBuilder } from 'vscode-languageserver';
+import {
+    CancellationToken,
+    Range,
+    SemanticTokens,
+    SemanticTokensBuilder
+} from 'vscode-languageserver';
 import { Document, mapRangeToOriginal } from '../../../lib/documents';
 import { SemanticTokensProvider } from '../../interfaces';
 import { SnapshotFragment } from '../DocumentSnapshot';
@@ -11,12 +16,19 @@ const CONTENT_LENGTH_LIMIT = 50000;
 export class SemanticTokensProviderImpl implements SemanticTokensProvider {
     constructor(private readonly lsAndTsDocResolver: LSAndTSDocResolver) {}
 
-    async getSemanticTokens(textDocument: Document, range?: Range): Promise<SemanticTokens | null> {
+    async getSemanticTokens(
+        textDocument: Document,
+        range?: Range,
+        cancellationToken?: CancellationToken
+    ): Promise<SemanticTokens | null> {
         const { lang, tsDoc } = await this.lsAndTsDocResolver.getLSAndTSDoc(textDocument);
         const fragment = await tsDoc.getFragment();
 
         // for better performance, don't do full-file semantic tokens when the file is too big
-        if (!range && fragment.text.length > CONTENT_LENGTH_LIMIT) {
+        if (
+            (!range && fragment.text.length > CONTENT_LENGTH_LIMIT) ||
+            cancellationToken?.isCancellationRequested
+        ) {
             return null;
         }
 
diff --git a/packages/language-server/src/plugins/typescript/features/SignatureHelpProvider.ts b/packages/language-server/src/plugins/typescript/features/SignatureHelpProvider.ts
index 82d900c77..194997713 100644
--- a/packages/language-server/src/plugins/typescript/features/SignatureHelpProvider.ts
+++ b/packages/language-server/src/plugins/typescript/features/SignatureHelpProvider.ts
@@ -6,7 +6,8 @@ import {
     SignatureHelpTriggerKind,
     SignatureInformation,
     ParameterInformation,
-    MarkupKind
+    MarkupKind,
+    CancellationToken
 } from 'vscode-languageserver';
 import { SignatureHelpProvider } from '../..';
 import { Document } from '../../../lib/documents';
@@ -22,11 +23,16 @@ export class SignatureHelpProviderImpl implements SignatureHelpProvider {
     async getSignatureHelp(
         document: Document,
         position: Position,
-        context: SignatureHelpContext | undefined
+        context: SignatureHelpContext | undefined,
+        cancellationToken?: CancellationToken
     ): Promise<SignatureHelp | null> {
         const { lang, tsDoc } = await this.lsAndTsDocResolver.getLSAndTSDoc(document);
         const fragment = await tsDoc.getFragment();
 
+        if (cancellationToken?.isCancellationRequested) {
+            return null;
+        }
+
         const offset = fragment.offsetAt(fragment.getGeneratedPosition(position));
         const triggerReason = this.toTsTriggerReason(context);
         const info = lang.getSignatureHelpItems(
diff --git a/packages/language-server/src/server.ts b/packages/language-server/src/server.ts
index 3aa029aa9..6933dc9c8 100644
--- a/packages/language-server/src/server.ts
+++ b/packages/language-server/src/server.ts
@@ -255,8 +255,8 @@ export function startServer(options?: LSOptions) {
         docManager.updateDocument(evt.textDocument, evt.contentChanges)
     );
     connection.onHover((evt) => pluginHost.doHover(evt.textDocument, evt.position));
-    connection.onCompletion((evt) =>
-        pluginHost.getCompletions(evt.textDocument, evt.position, evt.context)
+    connection.onCompletion((evt, cancellationToken) =>
+        pluginHost.getCompletions(evt.textDocument, evt.position, evt.context, cancellationToken)
     );
     connection.onDocumentFormatting((evt) =>
         pluginHost.formatDocument(evt.textDocument, evt.options)
@@ -268,14 +268,16 @@ export function startServer(options?: LSOptions) {
     connection.onColorPresentation((evt) =>
         pluginHost.getColorPresentations(evt.textDocument, evt.range, evt.color)
     );
-    connection.onDocumentSymbol((evt) => pluginHost.getDocumentSymbols(evt.textDocument));
+    connection.onDocumentSymbol((evt, cancellationToken) =>
+        pluginHost.getDocumentSymbols(evt.textDocument, cancellationToken)
+    );
     connection.onDefinition((evt) => pluginHost.getDefinitions(evt.textDocument, evt.position));
     connection.onReferences((evt) =>
         pluginHost.findReferences(evt.textDocument, evt.position, evt.context)
     );
 
-    connection.onCodeAction((evt) =>
-        pluginHost.getCodeActions(evt.textDocument, evt.range, evt.context)
+    connection.onCodeAction((evt, cancellationToken) =>
+        pluginHost.getCodeActions(evt.textDocument, evt.range, evt.context, cancellationToken)
     );
     connection.onExecuteCommand(async (evt) => {
         const result = await pluginHost.executeCommand(
@@ -294,18 +296,18 @@ export function startServer(options?: LSOptions) {
         }
     });
 
-    connection.onCompletionResolve((completionItem) => {
+    connection.onCompletionResolve((completionItem, cancellationToken) => {
         const data = (completionItem as AppCompletionItem).data as TextDocumentIdentifier;
 
         if (!data) {
             return completionItem;
         }
 
-        return pluginHost.resolveCompletion(data, completionItem);
+        return pluginHost.resolveCompletion(data, completionItem, cancellationToken);
     });
 
-    connection.onSignatureHelp((evt) =>
-        pluginHost.getSignatureHelp(evt.textDocument, evt.position, evt.context)
+    connection.onSignatureHelp((evt, cancellationToken) =>
+        pluginHost.getSignatureHelp(evt.textDocument, evt.position, evt.context, cancellationToken)
     );
 
     connection.onSelectionRanges((evt) =>
@@ -343,11 +345,11 @@ export function startServer(options?: LSOptions) {
         updateAllDiagnostics();
     });
 
-    connection.onRequest(SemanticTokensRequest.type, (evt) =>
-        pluginHost.getSemanticTokens(evt.textDocument)
+    connection.onRequest(SemanticTokensRequest.type, (evt, cancellationToken) =>
+        pluginHost.getSemanticTokens(evt.textDocument, undefined, cancellationToken)
     );
-    connection.onRequest(SemanticTokensRangeRequest.type, (evt) =>
-        pluginHost.getSemanticTokens(evt.textDocument, evt.range)
+    connection.onRequest(SemanticTokensRangeRequest.type, (evt, cancellationToken) =>
+        pluginHost.getSemanticTokens(evt.textDocument, evt.range, cancellationToken)
     );
 
     connection.onRequest(
diff --git a/packages/language-server/test/plugins/PluginHost.test.ts b/packages/language-server/test/plugins/PluginHost.test.ts
index bfe733a35..ee89abfc0 100644
--- a/packages/language-server/test/plugins/PluginHost.test.ts
+++ b/packages/language-server/test/plugins/PluginHost.test.ts
@@ -80,10 +80,16 @@ describe('PluginHost', () => {
         });
 
         sinon.assert.calledOnce(plugin.getCompletions);
-        sinon.assert.calledWithExactly(plugin.getCompletions, document, pos, {
-            triggerKind: CompletionTriggerKind.TriggerCharacter,
-            triggerCharacter: '.'
-        });
+        sinon.assert.calledWithExactly(
+            plugin.getCompletions,
+            document,
+            pos,
+            {
+                triggerKind: CompletionTriggerKind.TriggerCharacter,
+                triggerCharacter: '.'
+            },
+            undefined
+        );
     });
 
     describe('getCompletions (incomplete)', () => {
diff --git a/packages/language-server/test/plugins/svelte/SveltePlugin.test.ts b/packages/language-server/test/plugins/svelte/SveltePlugin.test.ts
index 78646827c..188831cb3 100644
--- a/packages/language-server/test/plugins/svelte/SveltePlugin.test.ts
+++ b/packages/language-server/test/plugins/svelte/SveltePlugin.test.ts
@@ -1,7 +1,12 @@
 import * as assert from 'assert';
 import { SveltePlugin } from '../../../src/plugins';
 import { DocumentManager, Document } from '../../../src/lib/documents';
-import { Diagnostic, Range, DiagnosticSeverity } from 'vscode-languageserver';
+import {
+    Diagnostic,
+    Range,
+    DiagnosticSeverity,
+    CancellationTokenSource
+} from 'vscode-languageserver';
 import { LSConfigManager } from '../../../src/ls-config';
 import * as importPackage from '../../../src/importPackage';
 import sinon from 'sinon';
@@ -143,4 +148,50 @@ describe('Svelte Plugin', () => {
             });
         });
     });
+
+    it('can cancel completion before promise resolved', async () => {
+        const { plugin, document } = setup('{#');
+        const cancellationTokenSource = new CancellationTokenSource();
+
+        const completionsPromise = plugin.getCompletions(
+            document,
+            { line: 0, character: 2 },
+            undefined,
+            cancellationTokenSource.token
+        );
+
+        cancellationTokenSource.cancel();
+
+        assert.deepStrictEqual(await completionsPromise, null);
+    });
+
+    it('can cancel code action before promise resolved', async () => {
+        const { plugin, document } = setup('<a></a>');
+        const cancellationTokenSource = new CancellationTokenSource();
+        const range = {
+            start: { line: 0, character: 0 },
+            end: { line: 0, character: 7 }
+        };
+
+        const codeActionPromise = plugin.getCodeActions(
+            document,
+            range,
+            {
+                diagnostics: [
+                    {
+                        message: 'A11y: <a> element should have child content',
+                        code: 'a11y-missing-content',
+                        range,
+                        severity: DiagnosticSeverity.Warning,
+                        source: 'svelte'
+                    }
+                ]
+            },
+            cancellationTokenSource.token
+        );
+
+        cancellationTokenSource.cancel();
+
+        assert.deepStrictEqual(await codeActionPromise, []);
+    });
 });
diff --git a/packages/language-server/test/plugins/typescript/TypescriptPlugin.test.ts b/packages/language-server/test/plugins/typescript/TypescriptPlugin.test.ts
index 0fa3fe27b..3fc0ba311 100644
--- a/packages/language-server/test/plugins/typescript/TypescriptPlugin.test.ts
+++ b/packages/language-server/test/plugins/typescript/TypescriptPlugin.test.ts
@@ -2,7 +2,7 @@ import * as assert from 'assert';
 import * as path from 'path';
 import ts from 'typescript';
 import fs from 'fs';
-import { FileChangeType, Position, Range } from 'vscode-languageserver';
+import { CancellationTokenSource, FileChangeType, Position, Range } from 'vscode-languageserver';
 import { Document, DocumentManager } from '../../../src/lib/documents';
 import { LSConfigManager } from '../../../src/ls-config';
 import { LSAndTSDocResolver, TypeScriptPlugin } from '../../../src/plugins';
@@ -99,6 +99,15 @@ describe('TypescriptPlugin', () => {
         );
     });
 
+    it('can cancel document symbols before promise resolved', async () => {
+        const { plugin, document } = setup('documentsymbols.svelte');
+        const cancellationTokenSource = new CancellationTokenSource();
+        const symbolsPromise = plugin.getDocumentSymbols(document, cancellationTokenSource.token);
+
+        cancellationTokenSource.cancel();
+        assert.deepStrictEqual(await symbolsPromise, []);
+    });
+
     it('provides definitions within svelte doc', async () => {
         const { plugin, document } = setup('definitions.svelte');
 
diff --git a/packages/language-server/test/plugins/typescript/features/CodeActionsProvider.test.ts b/packages/language-server/test/plugins/typescript/features/CodeActionsProvider.test.ts
index 874deb7a6..882a922b5 100644
--- a/packages/language-server/test/plugins/typescript/features/CodeActionsProvider.test.ts
+++ b/packages/language-server/test/plugins/typescript/features/CodeActionsProvider.test.ts
@@ -10,7 +10,8 @@ import {
     Position,
     CodeActionKind,
     TextDocumentEdit,
-    CodeAction
+    CodeAction,
+    CancellationTokenSource
 } from 'vscode-languageserver';
 import { CompletionsProviderImpl } from '../../../../src/plugins/typescript/features/CompletionProvider';
 import { LSConfigManager } from '../../../../src/ls-config';
@@ -795,4 +796,46 @@ describe('CodeActionsProvider', () => {
             ]
         });
     });
+
+    it('can cancel quick fix before promise resolved', async () => {
+        const { provider, document } = setup('codeactions.svelte');
+        const cancellationTokenSource = new CancellationTokenSource();
+
+        const codeActionsPromise = provider.getCodeActions(
+            document,
+            Range.create(Position.create(6, 4), Position.create(6, 5)),
+            {
+                diagnostics: [
+                    {
+                        code: 6133,
+                        message: "'a' is declared but its value is never read.",
+                        range: Range.create(Position.create(6, 4), Position.create(6, 5)),
+                        source: 'ts'
+                    }
+                ],
+                only: [CodeActionKind.QuickFix]
+            },
+            cancellationTokenSource.token
+        );
+
+        cancellationTokenSource.cancel();
+
+        assert.deepStrictEqual(await codeActionsPromise, []);
+    });
+
+    it('can cancel refactor before promise resolved', async () => {
+        const { provider, document } = setup('codeactions.svelte');
+        const cancellationTokenSource = new CancellationTokenSource();
+
+        const codeActionsPromise = provider.getCodeActions(
+            document,
+            Range.create(Position.create(8, 8), Position.create(8, 42)),
+            { diagnostics: [], only: [CodeActionKind.Refactor] },
+            cancellationTokenSource.token
+        );
+
+        cancellationTokenSource.cancel();
+
+        assert.deepStrictEqual(await codeActionsPromise, []);
+    });
 });
diff --git a/packages/language-server/test/plugins/typescript/features/CompletionProvider.test.ts b/packages/language-server/test/plugins/typescript/features/CompletionProvider.test.ts
index 52f16378b..655da186f 100644
--- a/packages/language-server/test/plugins/typescript/features/CompletionProvider.test.ts
+++ b/packages/language-server/test/plugins/typescript/features/CompletionProvider.test.ts
@@ -12,7 +12,8 @@ import {
     Range,
     CompletionTriggerKind,
     MarkupKind,
-    TextEdit
+    TextEdit,
+    CancellationTokenSource
 } from 'vscode-languageserver';
 import {
     CompletionsProviderImpl,
@@ -723,6 +724,43 @@ describe('CompletionProviderImpl', () => {
         ]);
     });
 
+    it('can be canceled before promise resolved', async () => {
+        const { completionProvider, document } = setup('importcompletions1.svelte');
+        const cancellationTokenSource = new CancellationTokenSource();
+
+        const completionsPromise = completionProvider.getCompletions(
+            document,
+            Position.create(1, 3),
+            undefined,
+            cancellationTokenSource.token
+        );
+
+        cancellationTokenSource.cancel();
+
+        assert.deepStrictEqual(await completionsPromise, null);
+    });
+
+    it('can cancel completion resolving before promise resolved', async () => {
+        const { completionProvider, document } = setup('importcompletions1.svelte');
+        const cancellationTokenSource = new CancellationTokenSource();
+
+        const completions = await completionProvider.getCompletions(
+            document,
+            Position.create(1, 3)
+        );
+
+        const item = completions?.items.find((item) => item.label === 'blubb');
+
+        const completionResolvingPromise = completionProvider.resolveCompletion(
+            document,
+            item!,
+            cancellationTokenSource.token
+        );
+        cancellationTokenSource.cancel();
+
+        assert.deepStrictEqual((await completionResolvingPromise).additionalTextEdits, undefined);
+    });
+
     const testForJsDocTemplateCompletion = async (position: Position, newText: string) => {
         const { completionProvider, document } = setup('jsdoc-completions.svelte');
 
diff --git a/packages/language-server/test/plugins/typescript/features/SemanticTokensProvider.test.ts b/packages/language-server/test/plugins/typescript/features/SemanticTokensProvider.test.ts
index b596bb558..605a03f6e 100644
--- a/packages/language-server/test/plugins/typescript/features/SemanticTokensProvider.test.ts
+++ b/packages/language-server/test/plugins/typescript/features/SemanticTokensProvider.test.ts
@@ -1,7 +1,12 @@
 import path from 'path';
 import ts from 'typescript';
 import assert from 'assert';
-import { Position, Range, SemanticTokensBuilder } from 'vscode-languageserver';
+import {
+    CancellationTokenSource,
+    Position,
+    Range,
+    SemanticTokensBuilder
+} from 'vscode-languageserver';
 import { Document, DocumentManager } from '../../../../src/lib/documents';
 import { TokenModifier, TokenType } from '../../../../src/lib/semanticToken/semanticTokenLegend';
 import { LSConfigManager } from '../../../../src/ls-config';
@@ -53,6 +58,19 @@ describe('SemanticTokensProvider', () => {
         assertResult(data, getExpected(/* isFull */ false));
     });
 
+    it('can cancel semantic token before promise resolved', async () => {
+        const { provider, document } = setup();
+        const cancellationTokenSource = new CancellationTokenSource();
+        const tokenPromise = provider.getSemanticTokens(
+            document,
+            undefined,
+            cancellationTokenSource.token
+        );
+        cancellationTokenSource.cancel();
+
+        assert.deepStrictEqual(await tokenPromise, null);
+    });
+
     function getExpected(full: boolean) {
         const tokenDataScript: Array<{
             line: number;
diff --git a/packages/language-server/test/plugins/typescript/features/SignatureHelpProvider.test.ts b/packages/language-server/test/plugins/typescript/features/SignatureHelpProvider.test.ts
index 1d796400f..6db80024c 100644
--- a/packages/language-server/test/plugins/typescript/features/SignatureHelpProvider.test.ts
+++ b/packages/language-server/test/plugins/typescript/features/SignatureHelpProvider.test.ts
@@ -1,7 +1,12 @@
 import path from 'path';
 import assert from 'assert';
 import ts from 'typescript';
-import { MarkupKind, Position, SignatureHelp } from 'vscode-languageserver';
+import {
+    CancellationTokenSource,
+    MarkupKind,
+    Position,
+    SignatureHelp
+} from 'vscode-languageserver';
 import { Document, DocumentManager } from '../../../../src/lib/documents';
 import { SignatureHelpProviderImpl } from '../../../../src/plugins/typescript/features/SignatureHelpProvider';
 import { LSAndTSDocResolver } from '../../../../src/plugins/typescript/LSAndTSDocResolver';
@@ -96,4 +101,19 @@ describe('SignatureHelpProvider', () => {
 
         assert.equal(result, null);
     });
+
+    it('provide signature help with formatted documentation', async () => {
+        const { provider, document } = setup();
+        const cancellationTokenSource = new CancellationTokenSource();
+
+        const signatureHelpPromise = provider.getSignatureHelp(
+            document,
+            Position.create(3, 8),
+            undefined,
+            cancellationTokenSource.token
+        );
+        cancellationTokenSource.cancel();
+
+        assert.deepStrictEqual(await signatureHelpPromise, null);
+    });
 });
diff --git a/packages/svelte-check/package.json b/packages/svelte-check/package.json
index 5ac335bd0..081087f50 100644
--- a/packages/svelte-check/package.json
+++ b/packages/svelte-check/package.json
@@ -49,7 +49,7 @@
         "rollup-plugin-cleanup": "^3.0.0",
         "rollup-plugin-copy": "^3.0.0",
         "svelte-language-server": "*",
-        "vscode-languageserver": "7.0.0",
+        "vscode-languageserver": "7.1.0-next.4",
         "vscode-languageserver-protocol": "3.16.0",
         "vscode-languageserver-types": "3.16.0",
         "vscode-uri": "2.1.2"
diff --git a/yarn.lock b/yarn.lock
index d16f01af8..82b6810af 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -2614,6 +2614,11 @@ vscode-jsonrpc@6.0.0:
   resolved "https://registry.yarnpkg.com/vscode-jsonrpc/-/vscode-jsonrpc-6.0.0.tgz#108bdb09b4400705176b957ceca9e0880e9b6d4e"
   integrity sha512-wnJA4BnEjOSyFMvjZdpiOwhSq9uDoK8e/kpRJDTaMYzwlkrhG1fwDIZI94CLsLzlCK5cIbMMtFlJlfR57Lavmg==
 
+vscode-jsonrpc@6.1.0-next.2:
+  version "6.1.0-next.2"
+  resolved "https://registry.yarnpkg.com/vscode-jsonrpc/-/vscode-jsonrpc-6.1.0-next.2.tgz#b5b67028d551d486c4ac1ec139ffc29382b36a2e"
+  integrity sha512-nkiNDGI+Ytp7uj1lxHXddXCoEunhcry1D+KmVHBfUUgWT9jMF8ZJyH5KQObdF+OGAh7bXZxD/SV4uGwSCeHHWA==
+
 vscode-languageclient@^7.0.0:
   version "7.0.0"
   resolved "https://registry.yarnpkg.com/vscode-languageclient/-/vscode-languageclient-7.0.0.tgz#b505c22c21ffcf96e167799757fca07a6bad0fb2"
@@ -2631,6 +2636,14 @@ vscode-languageserver-protocol@3.16.0:
     vscode-jsonrpc "6.0.0"
     vscode-languageserver-types "3.16.0"
 
+vscode-languageserver-protocol@3.17.0-next.5:
+  version "3.17.0-next.5"
+  resolved "https://registry.yarnpkg.com/vscode-languageserver-protocol/-/vscode-languageserver-protocol-3.17.0-next.5.tgz#295ebd7c416d7224b57e4de43c4bfefcc8095f06"
+  integrity sha512-LFZ6WMB3iPezQAU9OnGoERzcIVKhcs0OLfD/NHcqSj3g1wgxuLUL5kSlZbbjFySQCmhzm6b0yb3hjTSeBtq1+w==
+  dependencies:
+    vscode-jsonrpc "6.1.0-next.2"
+    vscode-languageserver-types "3.17.0-next.1"
+
 vscode-languageserver-textdocument@^1.0.1:
   version "1.0.1"
   resolved "https://registry.yarnpkg.com/vscode-languageserver-textdocument/-/vscode-languageserver-textdocument-1.0.1.tgz#178168e87efad6171b372add1dea34f53e5d330f"
@@ -2641,12 +2654,17 @@ vscode-languageserver-types@3.16.0, vscode-languageserver-types@^3.15.1, vscode-
   resolved "https://registry.yarnpkg.com/vscode-languageserver-types/-/vscode-languageserver-types-3.16.0.tgz#ecf393fc121ec6974b2da3efb3155644c514e247"
   integrity sha512-k8luDIWJWyenLc5ToFQQMaSrqCHiLwyKPHKPQZ5zz21vM+vIVUSvsRpcbiECH4WR88K2XZqc4ScRcZ7nk/jbeA==
 
-vscode-languageserver@7.0.0:
-  version "7.0.0"
-  resolved "https://registry.yarnpkg.com/vscode-languageserver/-/vscode-languageserver-7.0.0.tgz#49b068c87cfcca93a356969d20f5d9bdd501c6b0"
-  integrity sha512-60HTx5ID+fLRcgdHfmz0LDZAXYEV68fzwG0JWwEPBode9NuMYTIxuYXPg4ngO8i8+Ou0lM7y6GzaYWbiDL0drw==
+vscode-languageserver-types@3.17.0-next.1:
+  version "3.17.0-next.1"
+  resolved "https://registry.yarnpkg.com/vscode-languageserver-types/-/vscode-languageserver-types-3.17.0-next.1.tgz#396348493ccf567f0c22538033ebf95da5c5e4e3"
+  integrity sha512-VGzh06oynbYa6JbTKUbxOEZN7CYEtWhN7DK5wfzUpeCJl8X8xZX39g2PVfpqXrIEduu7dcJgK007KgnX9tHNKA==
+
+vscode-languageserver@7.1.0-next.4:
+  version "7.1.0-next.4"
+  resolved "https://registry.yarnpkg.com/vscode-languageserver/-/vscode-languageserver-7.1.0-next.4.tgz#e9503af9d028dfc3a89e210646c265a087f46b8c"
+  integrity sha512-/65lxR/CuLJoOdzTjOTYUPWS7k5qzaWese4PObnWc6jwLryUrSa7DslYfaRXigh5/xr1nlaUZCcJwkpgM0wFvw==
   dependencies:
-    vscode-languageserver-protocol "3.16.0"
+    vscode-languageserver-protocol "3.17.0-next.5"
 
 vscode-nls@^5.0.0:
   version "5.0.0"