diff --git a/packages/react-devtools-core/src/launchEditor.js b/packages/react-devtools-core/src/editor.js
similarity index 90%
rename from packages/react-devtools-core/src/launchEditor.js
rename to packages/react-devtools-core/src/editor.js
index 94628be8582e4..26043f07f650d 100644
--- a/packages/react-devtools-core/src/launchEditor.js
+++ b/packages/react-devtools-core/src/editor.js
@@ -102,31 +102,44 @@ function guessEditor(): Array<string> {
 
 let childProcess = null;
 
-export default function launchEditor(
+export function getValidFilePath(
   maybeRelativePath: string,
-  lineNumber: number,
   absoluteProjectRoots: Array<string>
-) {
+): string | null {
   // We use relative paths at Facebook with deterministic builds.
   // This is why our internal tooling calls React DevTools with absoluteProjectRoots.
   // If the filename is absolute then we don't need to care about this.
-  let filePath;
   if (isAbsolute(maybeRelativePath)) {
     if (existsSync(maybeRelativePath)) {
-      filePath = maybeRelativePath;
+      return maybeRelativePath;
     }
   } else {
     for (let i = 0; i < absoluteProjectRoots.length; i++) {
       const projectRoot = absoluteProjectRoots[i];
       const joinedPath = join(projectRoot, maybeRelativePath);
       if (existsSync(joinedPath)) {
-        filePath = joinedPath;
-        break;
+        return joinedPath;
       }
     }
   }
 
-  if (!filePath) {
+  return null;
+}
+
+export function doesFilePathExist(
+  maybeRelativePath: string,
+  absoluteProjectRoots: Array<string>
+): boolean {
+  return getValidFilePath(maybeRelativePath, absoluteProjectRoots) !== null;
+}
+
+export function launchEditor(
+  maybeRelativePath: string,
+  lineNumber: number,
+  absoluteProjectRoots: Array<string>
+) {
+  const filePath = getValidFilePath(maybeRelativePath, absoluteProjectRoots);
+  if (filePath === null) {
     return;
   }
 
diff --git a/packages/react-devtools-core/src/standalone.js b/packages/react-devtools-core/src/standalone.js
index 27774b380d96d..a88691d77ed8c 100644
--- a/packages/react-devtools-core/src/standalone.js
+++ b/packages/react-devtools-core/src/standalone.js
@@ -14,7 +14,7 @@ import { Server } from 'ws';
 import { existsSync, readFileSync } from 'fs';
 import { installHook } from 'src/hook';
 import DevTools from 'src/devtools/views/DevTools';
-import launchEditor from './launchEditor';
+import { doesFilePathExist, launchEditor } from './editor';
 import { __DEBUG__ } from 'src/constants';
 
 import type { FrontendBridge } from 'src/bridge';
@@ -85,16 +85,31 @@ function reload() {
     root.render(
       createElement(DevTools, {
         bridge: ((bridge: any): FrontendBridge),
+        canViewElementSourceFunction,
         showTabBar: true,
         store: ((store: any): Store),
         warnIfLegacyBackendDetected: true,
         viewElementSourceFunction,
-        viewElementSourceRequiresFileLocation: true,
       })
     );
   }, 100);
 }
 
+function canViewElementSourceFunction(
+  inspectedElement: InspectedElement
+): boolean {
+  if (
+    inspectedElement.canViewSource === false ||
+    inspectedElement.source === null
+  ) {
+    return false;
+  }
+
+  const { source } = inspectedElement;
+
+  return doesFilePathExist(source.fileName, projectRoots);
+}
+
 function viewElementSourceFunction(
   id: number,
   inspectedElement: InspectedElement
@@ -171,10 +186,7 @@ function initialize(socket: WebSocket) {
     socket.close();
   });
 
-  store = new Store(bridge, {
-    supportsNativeInspection: false,
-    supportsViewSource: projectRoots.length > 0,
-  });
+  store = new Store(bridge, { supportsNativeInspection: false });
 
   log('Connected');
   reload();
diff --git a/src/devtools/store.js b/src/devtools/store.js
index b843831e1deee..adaccfe24b27b 100644
--- a/src/devtools/store.js
+++ b/src/devtools/store.js
@@ -49,7 +49,6 @@ type Config = {|
   supportsNativeInspection?: boolean,
   supportsReloadAndProfile?: boolean,
   supportsProfiling?: boolean,
-  supportsViewSource?: boolean,
 |};
 
 export type Capabilities = {|
@@ -125,7 +124,6 @@ export default class Store extends EventEmitter<{|
   _supportsNativeInspection: boolean = false;
   _supportsProfiling: boolean = false;
   _supportsReloadAndProfile: boolean = false;
-  _supportsViewSource: boolean = true;
 
   // Total number of visible elements (within all roots).
   // Used for windowing purposes.
@@ -157,7 +155,6 @@ export default class Store extends EventEmitter<{|
         supportsNativeInspection,
         supportsProfiling,
         supportsReloadAndProfile,
-        supportsViewSource,
       } = config;
       if (supportsCaptureScreenshots) {
         this._supportsCaptureScreenshots = true;
@@ -165,7 +162,6 @@ export default class Store extends EventEmitter<{|
           localStorageGetItem(LOCAL_STORAGE_CAPTURE_SCREENSHOTS_KEY) === 'true';
       }
       this._supportsNativeInspection = supportsNativeInspection !== false;
-      this._supportsViewSource = supportsViewSource !== false;
       if (supportsProfiling) {
         this._supportsProfiling = true;
       }
@@ -365,10 +361,6 @@ export default class Store extends EventEmitter<{|
     return this._supportsReloadAndProfile && this._isBackendStorageAPISupported;
   }
 
-  get supportsViewSource(): boolean {
-    return this._supportsViewSource;
-  }
-
   containsElement(id: number): boolean {
     return this._idToElement.get(id) != null;
   }
diff --git a/src/devtools/views/Components/SelectedElement.js b/src/devtools/views/Components/SelectedElement.js
index 957d844421842..30e9bd527014d 100644
--- a/src/devtools/views/Components/SelectedElement.js
+++ b/src/devtools/views/Components/SelectedElement.js
@@ -34,9 +34,10 @@ export type Props = {||};
 export default function SelectedElement(_: Props) {
   const { inspectedElementID } = useContext(TreeStateContext);
   const dispatch = useContext(TreeDispatcherContext);
-  const { isFileLocationRequired, viewElementSourceFunction } = useContext(
-    ViewElementSourceContext
-  );
+  const {
+    canViewElementSourceFunction,
+    viewElementSourceFunction,
+  } = useContext(ViewElementSourceContext);
   const bridge = useContext(BridgeContext);
   const store = useContext(StoreContext);
   const { dispatch: modalDialogDispatch } = useContext(ModalDialogContext);
@@ -90,11 +91,14 @@ export default function SelectedElement(_: Props) {
     }
   }, [inspectedElement, viewElementSourceFunction]);
 
+  // In some cases (e.g. FB internal usage) the standalone shell might not be able to view the source.
+  // To detect this case, we defer to an injected helper function (if present).
   const canViewSource =
-    inspectedElement &&
+    inspectedElement !== null &&
     inspectedElement.canViewSource &&
     viewElementSourceFunction !== null &&
-    (!isFileLocationRequired || inspectedElement.source !== null);
+    (canViewElementSourceFunction === null ||
+      canViewElementSourceFunction(inspectedElement));
 
   const isSuspended =
     element !== null &&
@@ -201,16 +205,14 @@ export default function SelectedElement(_: Props) {
         >
           <ButtonIcon type="log-data" />
         </Button>
-        {store.supportsViewSource && (
-          <Button
-            className={styles.IconButton}
-            disabled={!canViewSource}
-            onClick={viewSource}
-            title="View source for this element"
-          >
-            <ButtonIcon type="view-source" />
-          </Button>
-        )}
+        <Button
+          className={styles.IconButton}
+          disabled={!canViewSource}
+          onClick={viewSource}
+          title="View source for this element"
+        >
+          <ButtonIcon type="view-source" />
+        </Button>
       </div>
 
       {inspectedElement === null && (
diff --git a/src/devtools/views/Components/ViewElementSourceContext.js b/src/devtools/views/Components/ViewElementSourceContext.js
index 0e76f7c56eb3f..30a3f017af20f 100644
--- a/src/devtools/views/Components/ViewElementSourceContext.js
+++ b/src/devtools/views/Components/ViewElementSourceContext.js
@@ -2,10 +2,13 @@
 
 import { createContext } from 'react';
 
-import type { ViewElementSource } from 'src/devtools/views/DevTools';
+import type {
+  CanViewElementSource,
+  ViewElementSource,
+} from 'src/devtools/views/DevTools';
 
 export type Context = {|
-  isFileLocationRequired: boolean,
+  canViewElementSourceFunction: CanViewElementSource | null,
   viewElementSourceFunction: ViewElementSource | null,
 |};
 
diff --git a/src/devtools/views/DevTools.js b/src/devtools/views/DevTools.js
index c63113dda54b6..0dd3bd3ed22d5 100644
--- a/src/devtools/views/DevTools.js
+++ b/src/devtools/views/DevTools.js
@@ -32,16 +32,19 @@ export type ViewElementSource = (
   id: number,
   inspectedElement: InspectedElement
 ) => void;
+export type CanViewElementSource = (
+  inspectedElement: InspectedElement
+) => boolean;
 
 export type Props = {|
   bridge: FrontendBridge,
   browserTheme?: BrowserTheme,
+  canViewElementSourceFunction?: ?CanViewElementSource,
   defaultTab?: TabID,
   showTabBar?: boolean,
   store: Store,
   warnIfLegacyBackendDetected?: boolean,
   viewElementSourceFunction?: ?ViewElementSource,
-  viewElementSourceRequiresFileLocation?: boolean,
 
   // This property is used only by the web extension target.
   // The built-in tab UI is hidden in that case, in favor of the browser's own panel tabs.
@@ -75,6 +78,7 @@ const tabs = [componentsTab, profilerTab];
 export default function DevTools({
   bridge,
   browserTheme = 'light',
+  canViewElementSourceFunction = null,
   defaultTab = 'components',
   componentsPortalContainer,
   overrideTab,
@@ -83,8 +87,7 @@ export default function DevTools({
   showTabBar = false,
   store,
   warnIfLegacyBackendDetected = false,
-  viewElementSourceFunction,
-  viewElementSourceRequiresFileLocation = false,
+  viewElementSourceFunction = null,
 }: Props) {
   const [tab, setTab] = useState(defaultTab);
   if (overrideTab != null && overrideTab !== tab) {
@@ -93,10 +96,10 @@ export default function DevTools({
 
   const viewElementSource = useMemo(
     () => ({
-      isFileLocationRequired: viewElementSourceRequiresFileLocation,
-      viewElementSourceFunction: viewElementSourceFunction || null,
+      canViewElementSourceFunction,
+      viewElementSourceFunction,
     }),
-    [viewElementSourceFunction, viewElementSourceRequiresFileLocation]
+    [canViewElementSourceFunction, viewElementSourceFunction]
   );
 
   return (