diff --git a/packages/language-server/package.json b/packages/language-server/package.json
index b3602776f..1b872a3c2 100644
--- a/packages/language-server/package.json
+++ b/packages/language-server/package.json
@@ -57,7 +57,7 @@
         "prettier-plugin-svelte": "~2.3.0",
         "source-map": "^0.7.3",
         "svelte": "~3.38.2",
-        "svelte-preprocess": "~4.6.1",
+        "svelte-preprocess": "~4.7.3",
         "svelte2tsx": "*",
         "typescript": "*",
         "vscode-css-languageservice": "5.0.0",
diff --git a/packages/language-server/test/plugins/svelte/testfiles/tsconfig.json b/packages/language-server/test/plugins/svelte/testfiles/tsconfig.json
new file mode 100644
index 000000000..ccbc2ad98
--- /dev/null
+++ b/packages/language-server/test/plugins/svelte/testfiles/tsconfig.json
@@ -0,0 +1,10 @@
+{
+    "compilerOptions": {
+        "strict": true,
+        /**
+          This is actually not needed, but makes the tests faster
+          because TS does not look up other types.
+        */
+        "types": ["svelte"]
+    }
+}
diff --git a/yarn.lock b/yarn.lock
index 7403a0a01..d16f01af8 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -2432,10 +2432,10 @@ svelte-preprocess@^4.0.0:
     detect-indent "^6.0.0"
     strip-indent "^3.0.0"
 
-svelte-preprocess@~4.6.1:
-  version "4.6.9"
-  resolved "https://registry.yarnpkg.com/svelte-preprocess/-/svelte-preprocess-4.6.9.tgz#073d923eb351b98b6c6a454ba5feee981cd9dbf5"
-  integrity sha512-SROWH0rB0DJ+0Ii264cprmNu/NJyZacs5wFD71ya93Cg/oA2lKHgQm4F6j0EWA4ktFMzeuJJm/eX6fka39hEHA==
+svelte-preprocess@~4.7.3:
+  version "4.7.3"
+  resolved "https://registry.yarnpkg.com/svelte-preprocess/-/svelte-preprocess-4.7.3.tgz#454fa059c2400b15e7a3caeca18993cff9df0e96"
+  integrity sha512-Zx1/xLeGOIBlZMGPRCaXtlMe4ZA0faato5Dc3CosEqwu75MIEPuOstdkH6cy+RYTUYynoxzNaDxkPX4DbrPwRA==
   dependencies:
     "@types/pug" "^2.0.4"
     "@types/sass" "^1.16.0"