diff --git a/extensions/ql-vscode/eslint.config.mjs b/extensions/ql-vscode/eslint.config.mjs
index 9496fb03876..e453a1f9838 100644
--- a/extensions/ql-vscode/eslint.config.mjs
+++ b/extensions/ql-vscode/eslint.config.mjs
@@ -69,7 +69,6 @@ export default tseslint.config(
 
       // Rules disabled during eslint 9 migration
       "github/filenames-match-regex": "off",
-      "@typescript-eslint/restrict-template-expressions": "off",
       "@typescript-eslint/no-unsafe-assignment": "off",
       "@typescript-eslint/no-unsafe-argument": "off",
       "@typescript-eslint/no-unsafe-member-access": "off",
diff --git a/extensions/ql-vscode/src/codeql-cli/cli.ts b/extensions/ql-vscode/src/codeql-cli/cli.ts
index 2074f0d7dec..27a61c4a143 100644
--- a/extensions/ql-vscode/src/codeql-cli/cli.ts
+++ b/extensions/ql-vscode/src/codeql-cli/cli.ts
@@ -314,7 +314,7 @@ export class CodeQLCliServer implements Disposable {
       } catch (e) {
         // We are probably fine here, the process has already closed stdin.
         void this.logger.log(
-          `Shutdown request failed: process stdin may have already closed. The error was ${e}`,
+          `Shutdown request failed: process stdin may have already closed. The error was ${getErrorMessage(e)}`,
         );
         void this.logger.log("Stopping the process anyway.");
       }
@@ -748,7 +748,7 @@ export class CodeQLCliServer implements Disposable {
           } else {
             reject(
               new Error(
-                `${command} ${commandArgs.join(" ")} failed with code ${code}`,
+                `${command.join(" ")} ${commandArgs.join(" ")} failed with code ${code}`,
               ),
             );
           }
diff --git a/extensions/ql-vscode/src/codeql-cli/distribution.ts b/extensions/ql-vscode/src/codeql-cli/distribution.ts
index ba3050ca904..35bbb7acf16 100644
--- a/extensions/ql-vscode/src/codeql-cli/distribution.ts
+++ b/extensions/ql-vscode/src/codeql-cli/distribution.ts
@@ -385,7 +385,7 @@ class ExtensionSpecificDistributionManager {
       } catch (e) {
         void extLogger.log(
           "WARNING: Tried to remove corrupted CodeQL CLI at " +
-            `${this.getDistributionStoragePath()} but encountered an error: ${e}.`,
+            `${this.getDistributionStoragePath()} but encountered an error: ${getErrorMessage(e)}.`,
         );
       }
     }
@@ -457,7 +457,7 @@ class ExtensionSpecificDistributionManager {
     } catch (e) {
       void extLogger.log(
         `Tried to clean up old version of CLI at ${this.getDistributionStoragePath()} ` +
-          `but encountered an error: ${e}.`,
+          `but encountered an error: ${getErrorMessage(e)}.`,
       );
     }
 
diff --git a/extensions/ql-vscode/src/codeql-cli/query-language.ts b/extensions/ql-vscode/src/codeql-cli/query-language.ts
index 17430ee06a5..d5cef76e697 100644
--- a/extensions/ql-vscode/src/codeql-cli/query-language.ts
+++ b/extensions/ql-vscode/src/codeql-cli/query-language.ts
@@ -89,7 +89,7 @@ export async function askForLanguage(
   if (!isQueryLanguage(language)) {
     void showAndLogErrorMessage(
       extLogger,
-      `Language '${language}' is not supported. Only languages ${Object.values(
+      `Language '${language as string}' is not supported. Only languages ${Object.values(
         QueryLanguage,
       ).join(", ")} are supported.`,
     );
diff --git a/extensions/ql-vscode/src/codeql-cli/query-metadata.ts b/extensions/ql-vscode/src/codeql-cli/query-metadata.ts
index 0991bf952d3..88fe52d49ba 100644
--- a/extensions/ql-vscode/src/codeql-cli/query-metadata.ts
+++ b/extensions/ql-vscode/src/codeql-cli/query-metadata.ts
@@ -1,6 +1,7 @@
 import type { CodeQLCliServer } from "./cli";
 import type { QueryMetadata } from "../common/interface-types";
 import { extLogger } from "../common/logging/vscode";
+import { getErrorMessage } from "../common/helpers-pure";
 
 /**
  * Gets metadata for a query, if it exists.
@@ -16,7 +17,9 @@ export async function tryGetQueryMetadata(
     return await cliServer.resolveMetadata(queryPath);
   } catch (e) {
     // Ignore errors and provide no metadata.
-    void extLogger.log(`Couldn't resolve metadata for ${queryPath}: ${e}`);
+    void extLogger.log(
+      `Couldn't resolve metadata for ${queryPath}: ${getErrorMessage(e)}`,
+    );
     return;
   }
 }
diff --git a/extensions/ql-vscode/src/common/short-paths.ts b/extensions/ql-vscode/src/common/short-paths.ts
index 0025b96da05..860544c38d4 100644
--- a/extensions/ql-vscode/src/common/short-paths.ts
+++ b/extensions/ql-vscode/src/common/short-paths.ts
@@ -92,12 +92,12 @@ async function expandShortPathComponent(
         }
       } catch (e) {
         // Can't read stats for the child, so skip it.
-        void logger.log(`Error reading stats for child: ${e}`);
+        void logger.log(`Error reading stats for child: ${getErrorMessage(e)}`);
       }
     }
   } catch (e) {
     // Can't read the directory, so we won't be able to find this in the directory listing.
-    void logger.log(`Error reading directory: ${e}`);
+    void logger.log(`Error reading directory: ${getErrorMessage(e)}`);
     return shortBase;
   }
 
diff --git a/extensions/ql-vscode/src/common/vscode/archive-filesystem-provider.ts b/extensions/ql-vscode/src/common/vscode/archive-filesystem-provider.ts
index c82225f42f1..1ee61468c36 100644
--- a/extensions/ql-vscode/src/common/vscode/archive-filesystem-provider.ts
+++ b/extensions/ql-vscode/src/common/vscode/archive-filesystem-provider.ts
@@ -135,7 +135,7 @@ const sourceArchiveUriAuthorityPattern = /^(\d+)-(\d+)$/;
 class InvalidSourceArchiveUriError extends Error {
   constructor(uri: Uri) {
     super(
-      `Can't decode uri ${uri}: authority should be of the form startIndex-endIndex (where both indices are integers).`,
+      `Can't decode uri ${uri.toString()}: authority should be of the form startIndex-endIndex (where both indices are integers).`,
     );
   }
 }
diff --git a/extensions/ql-vscode/src/common/vscode/webview-html.ts b/extensions/ql-vscode/src/common/vscode/webview-html.ts
index 9a02714f726..e1eac40024c 100644
--- a/extensions/ql-vscode/src/common/vscode/webview-html.ts
+++ b/extensions/ql-vscode/src/common/vscode/webview-html.ts
@@ -89,7 +89,7 @@ export function getHtmlForWebview(
   <body>
     <div id=root data-view="${view}">
     </div>
-      <script nonce="${nonce}" src="${scriptWebviewUri}">
+      <script nonce="${nonce}" src="${scriptWebviewUri.toString()}">
     </script>
   </body>
 </html>`;
@@ -101,9 +101,9 @@ function getNonce(): string {
 }
 
 function createStylesLinkWithNonce(nonce: string, uri: Uri): string {
-  return `<link nonce="${nonce}" rel="stylesheet" href="${uri}">`;
+  return `<link nonce="${nonce}" rel="stylesheet" href="${uri.toString()}">`;
 }
 
 function createStylesLinkWithoutNonce(uri: Uri): string {
-  return `<link rel="stylesheet" href="${uri}">`;
+  return `<link rel="stylesheet" href="${uri.toString()}">`;
 }
diff --git a/extensions/ql-vscode/src/databases/local-databases-ui.ts b/extensions/ql-vscode/src/databases/local-databases-ui.ts
index d1ed2147fe7..823093bfe49 100644
--- a/extensions/ql-vscode/src/databases/local-databases-ui.ts
+++ b/extensions/ql-vscode/src/databases/local-databases-ui.ts
@@ -380,7 +380,7 @@ export class DatabaseUI extends DisposableObject {
             // This specifically refers to the database folder in
             // https://github.com/github/codespaces-codeql
             const uri = Uri.parse(
-              `${workspace.workspaceFolders[0].uri}/.tours/codeql-tutorial-database`,
+              `${workspace.workspaceFolders[0].uri.toString()}/.tours/codeql-tutorial-database`,
             );
 
             const databaseItem = this.databaseManager.findDatabaseItem(uri);
@@ -1062,14 +1062,14 @@ export class DatabaseUI extends DisposableObject {
 
       if (!validFileTypes.includes(entry[1])) {
         void this.app.logger.log(
-          `Skipping import for '${entry}', invalid file type: ${entry[1]}`,
+          `Skipping import for '${entry[0]}', invalid file type: ${entry[1]}`,
         );
         continue;
       }
 
       try {
         const databaseUri = Uri.joinPath(uri, entry[0]);
-        void this.app.logger.log(`Importing from ${databaseUri}`);
+        void this.app.logger.log(`Importing from ${databaseUri.toString()}`);
 
         const database = await this.importDatabase(
           databaseUri,
diff --git a/extensions/ql-vscode/src/databases/local-databases/database-manager.ts b/extensions/ql-vscode/src/databases/local-databases/database-manager.ts
index 643c601cd3e..5685f5f997a 100644
--- a/extensions/ql-vscode/src/databases/local-databases/database-manager.ts
+++ b/extensions/ql-vscode/src/databases/local-databases/database-manager.ts
@@ -64,12 +64,13 @@ const DB_LIST = "databaseList";
  */
 function eventFired<T>(
   event: vscode.Event<T>,
+  eventName: string,
   timeoutMs = 1000,
 ): Promise<T | undefined> {
   return new Promise((res, _rej) => {
     const timeout = setTimeout(() => {
       void extLogger.log(
-        `Waiting for event ${event} timed out after ${timeoutMs}ms`,
+        `Waiting for event '${eventName}' timed out after ${timeoutMs}ms`,
       );
       res(undefined);
       dispose();
@@ -256,7 +257,7 @@ export class DatabaseManager extends DisposableObject {
   private async reimportTestDatabase(databaseUri: vscode.Uri): Promise<void> {
     const dbItem = this.findDatabaseItem(databaseUri);
     if (dbItem === undefined || dbItem.origin?.type !== "testproj") {
-      throw new Error(`Database ${databaseUri} is not a testproj.`);
+      throw new Error(`Database ${databaseUri.toString()} is not a testproj.`);
     }
 
     await this.removeDatabaseItem(dbItem);
@@ -474,7 +475,10 @@ export class DatabaseManager extends DisposableObject {
       });
       // vscode api documentation says we must to wait for this event
       // between multiple `updateWorkspaceFolders` calls.
-      await eventFired(vscode.workspace.onDidChangeWorkspaceFolders);
+      await eventFired(
+        vscode.workspace.onDidChangeWorkspaceFolders,
+        "vscode.workspace.onDidChangeWorkspaceFolders",
+      );
     }
   }
 
@@ -561,7 +565,7 @@ export class DatabaseManager extends DisposableObject {
             // When loading from persisted state, leave invalid databases in the list. They will be
             // marked as invalid, and cannot be set as the current database.
             void this.logger.log(
-              `Error loading database ${database.uri}: ${e}.`,
+              `Error loading database ${database.uri}: ${getErrorMessage(e)}.`,
             );
           }
         }
diff --git a/extensions/ql-vscode/src/extension.ts b/extensions/ql-vscode/src/extension.ts
index 3edd7b8944f..bd73929ad63 100644
--- a/extensions/ql-vscode/src/extension.ts
+++ b/extensions/ql-vscode/src/extension.ts
@@ -218,7 +218,7 @@ function getCommands(
     "codeQL.copyVersion": async () => {
       const text = `CodeQL extension version: ${
         extension?.packageJSON.version
-      } \nCodeQL CLI version: ${await getCliVersion()} \nPlatform: ${platform()} ${arch()}`;
+      } \nCodeQL CLI version: ${(await getCliVersion()).toString()} \nPlatform: ${platform()} ${arch()}`;
       await env.clipboard.writeText(text);
       void showAndLogInformationMessage(extLogger, text);
     },
@@ -457,8 +457,8 @@ export async function activate(
 
       void showAndLogWarningMessage(
         extLogger,
-        `You are using an unsupported version of the CodeQL CLI (${ver.version}). ` +
-          `The minimum supported version is ${CliVersionConstraint.OLDEST_SUPPORTED_CLI_VERSION}. ` +
+        `You are using an unsupported version of the CodeQL CLI (${ver.version.toString()}). ` +
+          `The minimum supported version is ${CliVersionConstraint.OLDEST_SUPPORTED_CLI_VERSION.toString()}. ` +
           `Please upgrade to a newer version of the CodeQL CLI.`,
       );
       unsupportedWarningShown = true;
@@ -615,10 +615,13 @@ async function installOrUpdateDistribution(
     } else if (e instanceof GithubApiError) {
       void alertFunction(
         extLogger,
-        `Encountered GitHub API error while trying to ${taskDescription}. ${e}`,
+        `Encountered GitHub API error while trying to ${taskDescription}. ${getErrorMessage(e)}`,
       );
     }
-    void alertFunction(extLogger, `Unable to ${taskDescription}. ${e}`);
+    void alertFunction(
+      extLogger,
+      `Unable to ${taskDescription}. ${getErrorMessage(e)}`,
+    );
   } finally {
     isInstallingOrUpdatingDistribution = false;
   }
@@ -640,11 +643,11 @@ async function getDistributionDisplayingDistributionWarnings(
           case DistributionKind.ExtensionManaged:
             return 'Please update the CodeQL CLI by running the "CodeQL: Check for CLI Updates" command.';
           case DistributionKind.CustomPathConfig:
-            return `Please update the "CodeQL CLI Executable Path" setting to point to a CLI in the version range ${codeQlVersionRange}.`;
+            return `Please update the "CodeQL CLI Executable Path" setting to point to a CLI in the version range ${codeQlVersionRange.toString()}.`;
           case DistributionKind.PathEnvironmentVariable:
             return (
-              `Please update the CodeQL CLI on your PATH to a version compatible with ${codeQlVersionRange}, or ` +
-              `set the "CodeQL CLI Executable Path" setting to the path of a CLI version compatible with ${codeQlVersionRange}.`
+              `Please update the CodeQL CLI on your PATH to a version compatible with ${codeQlVersionRange.toString()}, or ` +
+              `set the "CodeQL CLI Executable Path" setting to the path of a CLI version compatible with ${codeQlVersionRange.toString()}.`
             );
         }
       })();
diff --git a/extensions/ql-vscode/src/language-support/ast-viewer/ast-viewer.ts b/extensions/ql-vscode/src/language-support/ast-viewer/ast-viewer.ts
index 71c057aa62c..f186674c08e 100644
--- a/extensions/ql-vscode/src/language-support/ast-viewer/ast-viewer.ts
+++ b/extensions/ql-vscode/src/language-support/ast-viewer/ast-viewer.ts
@@ -80,11 +80,11 @@ class AstViewerDataProvider
     const treeItem = new TreeItem(item.label || "", state);
     treeItem.description = line ? `Line ${line}` : "";
     treeItem.id = String(item.id);
-    treeItem.tooltip = `${treeItem.description} ${treeItem.label}`;
+    treeItem.tooltip = `${treeItem.description} ${typeof treeItem.label === "string" ? treeItem.label : (treeItem.label?.label ?? "")}`;
     treeItem.command = {
       command: "codeQLAstViewer.gotoCode",
       title: "Go To Code",
-      tooltip: `Go To ${item.location}`,
+      tooltip: "Go To Code",
       arguments: [item],
     };
     return treeItem;
diff --git a/extensions/ql-vscode/src/language-support/query-editor.ts b/extensions/ql-vscode/src/language-support/query-editor.ts
index 71e66900037..a7567e1f1be 100644
--- a/extensions/ql-vscode/src/language-support/query-editor.ts
+++ b/extensions/ql-vscode/src/language-support/query-editor.ts
@@ -99,7 +99,7 @@ async function previewQueryHelp(
         telemetryListener,
         errorMessage,
         {
-          fullMessage: `${errorMessage}\n${getErrorMessage(e)}`,
+          fullMessage: `${errorMessage.fullMessage}\n${getErrorMessage(e)}`,
         },
       );
     }
diff --git a/extensions/ql-vscode/src/local-queries/results-view.ts b/extensions/ql-vscode/src/local-queries/results-view.ts
index 00eae1138aa..55480c344f8 100644
--- a/extensions/ql-vscode/src/local-queries/results-view.ts
+++ b/extensions/ql-vscode/src/local-queries/results-view.ts
@@ -955,7 +955,9 @@ export class ResultsView extends AbstractWebview<
       }
       const resultLocation = tryResolveLocation(sarifLoc, databaseItem);
       if (!resultLocation) {
-        void this.logger.log(`Sarif location was not resolvable ${sarifLoc}`);
+        void this.logger.log(
+          `Sarif location was not resolvable: ${sarifLoc.uri.toString()}`,
+        );
         continue;
       }
       const parsedMessage = parseSarifPlainTextMessage(message);
diff --git a/extensions/ql-vscode/src/query-evaluation-logging/eval-log-viewer.ts b/extensions/ql-vscode/src/query-evaluation-logging/eval-log-viewer.ts
index a35b1cd72c4..0bd7a572b44 100644
--- a/extensions/ql-vscode/src/query-evaluation-logging/eval-log-viewer.ts
+++ b/extensions/ql-vscode/src/query-evaluation-logging/eval-log-viewer.ts
@@ -45,7 +45,10 @@ class EvalLogDataProvider
       ? TreeItemCollapsibleState.Collapsed
       : TreeItemCollapsibleState.None;
     const treeItem = new TreeItem(element.label || "", state);
-    treeItem.tooltip = `${treeItem.label} || ''}`;
+    treeItem.tooltip =
+      typeof treeItem.label === "string"
+        ? treeItem.label
+        : (treeItem.label?.label ?? "");
     return treeItem;
   }
 
diff --git a/extensions/ql-vscode/src/query-history/query-history-scrubber.ts b/extensions/ql-vscode/src/query-history/query-history-scrubber.ts
index 961124116b6..1e31ccdf300 100644
--- a/extensions/ql-vscode/src/query-history/query-history-scrubber.ts
+++ b/extensions/ql-vscode/src/query-history/query-history-scrubber.ts
@@ -113,7 +113,9 @@ async function scrubQueries(
         throw new Error(EOL + errors.join(EOL));
       }
     } catch (e) {
-      void extLogger.log(`Error while scrubbing queries: ${e}`);
+      void extLogger.log(
+        `Error while scrubbing queries: ${getErrorMessage(e)}`,
+      );
     } finally {
       void extLogger.log(`Scrubbed ${scrubCount} old queries.`);
     }
diff --git a/extensions/ql-vscode/src/query-testing/test-runner.ts b/extensions/ql-vscode/src/query-testing/test-runner.ts
index f0d8aaa39e0..8c38fca4ab6 100644
--- a/extensions/ql-vscode/src/query-testing/test-runner.ts
+++ b/extensions/ql-vscode/src/query-testing/test-runner.ts
@@ -125,7 +125,7 @@ export class TestRunner extends DisposableObject {
           // So we need to display the error message ourselves and then rethrow.
           void showAndLogWarningMessage(
             extLogger,
-            `Cannot reopen database ${uri}: ${e}`,
+            `Cannot reopen database ${uri.toString()}: ${getErrorMessage(e)}`,
           );
           throw e;
         }
diff --git a/extensions/ql-vscode/src/run-queries-shared.ts b/extensions/ql-vscode/src/run-queries-shared.ts
index 4e463812cb0..03e25df46dc 100644
--- a/extensions/ql-vscode/src/run-queries-shared.ts
+++ b/extensions/ql-vscode/src/run-queries-shared.ts
@@ -225,7 +225,7 @@ export class QueryEvaluationInfo extends QueryOutputDir {
             .map((v, i) => {
               if (chunk.columns[i].kind === "String") {
                 return `"${
-                  typeof v === "string" ? v.replaceAll('"', '""') : v
+                  typeof v === "string" ? v.replaceAll('"', '""') : v.toString()
                 }"`;
               } else if (chunk.columns[i].kind === "Entity") {
                 return (v as BqrsEntityValue).label;
diff --git a/extensions/ql-vscode/src/status-bar.ts b/extensions/ql-vscode/src/status-bar.ts
index 4dd9f2523c2..66b7d2270c3 100644
--- a/extensions/ql-vscode/src/status-bar.ts
+++ b/extensions/ql-vscode/src/status-bar.ts
@@ -55,7 +55,7 @@ export class CodeQlStatusBarHandler extends DisposableObject {
     this.item.text = `CodeQL${canary}`;
 
     const version = await this.cli.getVersion();
-    this.item.text = `CodeQL CLI v${version}${canary}`;
+    this.item.text = `CodeQL CLI v${version.toString()}${canary}`;
     this.item.show();
   }
 }
diff --git a/extensions/ql-vscode/src/tmp-dir.ts b/extensions/ql-vscode/src/tmp-dir.ts
index b556150a0df..51b1cc814ec 100644
--- a/extensions/ql-vscode/src/tmp-dir.ts
+++ b/extensions/ql-vscode/src/tmp-dir.ts
@@ -1,5 +1,6 @@
 import { dirSync } from "tmp-promise";
 import { extLogger } from "./common/logging/vscode";
+import { getErrorMessage } from "./common/helpers-pure";
 
 // Shared temporary folder for the extension.
 export const tmpDir = dirSync({
@@ -14,7 +15,7 @@ export const tmpDirDisposal = {
       tmpDir.removeCallback();
     } catch (e) {
       void extLogger.log(
-        `Failed to remove temporary directory ${tmpDir.name}: ${e}`,
+        `Failed to remove temporary directory ${tmpDir.name}: ${getErrorMessage(e)}`,
       );
     }
   },
diff --git a/extensions/ql-vscode/src/variant-analysis/gh-api/gh-api-client.ts b/extensions/ql-vscode/src/variant-analysis/gh-api/gh-api-client.ts
index 24abc989a4b..be8d323c7c4 100644
--- a/extensions/ql-vscode/src/variant-analysis/gh-api/gh-api-client.ts
+++ b/extensions/ql-vscode/src/variant-analysis/gh-api/gh-api-client.ts
@@ -99,9 +99,9 @@ export async function createGist(
   });
   if (response.status >= 300) {
     throw new Error(
-      `Error exporting variant analysis results: ${response.status} ${
-        response?.data || ""
-      }`,
+      `Error exporting variant analysis results: ${response.status} ${JSON.stringify(
+        response?.data,
+      )}`,
     );
   }
   return response.data.html_url;
diff --git a/extensions/ql-vscode/src/variant-analysis/sarif-processing.ts b/extensions/ql-vscode/src/variant-analysis/sarif-processing.ts
index 728fc90d41f..f998f228e19 100644
--- a/extensions/ql-vscode/src/variant-analysis/sarif-processing.ts
+++ b/extensions/ql-vscode/src/variant-analysis/sarif-processing.ts
@@ -24,6 +24,7 @@ import type {
   ResultSeverity,
   ThreadFlow,
 } from "./shared/analysis-result";
+import { getErrorMessage } from "../common/helpers-pure";
 
 // A line of more than 8k characters is probably generated.
 const CODE_SNIPPET_LARGE_LINE_SIZE_LIMIT = 8192;
@@ -47,7 +48,9 @@ export function extractAnalysisAlerts(
       try {
         alerts.push(...extractResultAlerts(run, result, fileLinkPrefix));
       } catch (e) {
-        errors.push(`Error when processing SARIF result: ${e}`);
+        errors.push(
+          `Error when processing SARIF result: ${getErrorMessage(e)}`,
+        );
         continue;
       }
     }
diff --git a/extensions/ql-vscode/src/variant-analysis/variant-analysis-manager.ts b/extensions/ql-vscode/src/variant-analysis/variant-analysis-manager.ts
index 9bb707a9775..4256d037cfc 100644
--- a/extensions/ql-vscode/src/variant-analysis/variant-analysis-manager.ts
+++ b/extensions/ql-vscode/src/variant-analysis/variant-analysis-manager.ts
@@ -332,7 +332,7 @@ export class VariantAnalysisManager
   ): Promise<number | undefined> {
     if (!isVariantAnalysisEnabledForGitHubHost()) {
       throw new Error(
-        `Multi-repository variant analysis is not enabled for ${getEnterpriseUri()}`,
+        `Multi-repository variant analysis is not enabled for ${getEnterpriseUri()?.toString()}`,
       );
     }
 
diff --git a/extensions/ql-vscode/src/variant-analysis/view-autofixes.ts b/extensions/ql-vscode/src/variant-analysis/view-autofixes.ts
index 16bbac07bd8..0d0214b07cf 100644
--- a/extensions/ql-vscode/src/variant-analysis/view-autofixes.ts
+++ b/extensions/ql-vscode/src/variant-analysis/view-autofixes.ts
@@ -777,7 +777,9 @@ function execAutofix(
     try {
       const cwd = options?.cwd || process.cwd();
       if (showCommand) {
-        void extLogger.log(`Spawning '${bin} ${args.join(" ")}' in ${cwd}`);
+        void extLogger.log(
+          `Spawning '${bin} ${args.join(" ")}' in ${cwd.toString()}`,
+        );
       }
 
       let stdoutBuffer = "";
diff --git a/extensions/ql-vscode/test/vscode-tests/jest.activated-extension.setup.ts b/extensions/ql-vscode/test/vscode-tests/jest.activated-extension.setup.ts
index 5085fc19460..dc47c409111 100644
--- a/extensions/ql-vscode/test/vscode-tests/jest.activated-extension.setup.ts
+++ b/extensions/ql-vscode/test/vscode-tests/jest.activated-extension.setup.ts
@@ -8,6 +8,7 @@ import {
   setStoragePath,
   storagePath,
 } from "./global.helper";
+import { getErrorMessage } from "../../src/common/helpers-pure";
 
 if (process.env.CI) {
   jest.retryTimes(3, {
@@ -50,6 +51,8 @@ export async function afterAllAction() {
   } catch (e) {
     // we are exiting anyway so don't worry about it.
     // most likely the directory this is a test on Windows and some files are locked.
-    console.warn(`Failed to remove storage directory '${storagePath}': ${e}`);
+    console.warn(
+      `Failed to remove storage directory '${storagePath}': ${getErrorMessage(e)}`,
+    );
   }
 }