diff --git a/src/common/urlUtils.ts b/src/common/urlUtils.ts
index 8ee9f7d4e..a33677f6c 100644
--- a/src/common/urlUtils.ts
+++ b/src/common/urlUtils.ts
@@ -199,6 +199,15 @@ export function completeUrlEscapingRoot(base: string | undefined, relative: stri
 }
 
 export function isValidUrl(url: string): boolean {
+  try {
+    new URL(url);
+    return true;
+  } catch (e) {
+    return false;
+  }
+}
+
+export function isValidUrlWithProtocol(url: string): boolean {
   try {
     const parsed = new URL(url);
 
diff --git a/src/targets/browser/browserPathResolver.ts b/src/targets/browser/browserPathResolver.ts
index bdf5347a1..ab925d3ef 100644
--- a/src/targets/browser/browserPathResolver.ts
+++ b/src/targets/browser/browserPathResolver.ts
@@ -22,7 +22,7 @@ import {
 } from '../../common/sourceMaps/sourceMapResolutionUtils';
 import { IUrlResolution } from '../../common/sourcePathResolver';
 import * as utils from '../../common/urlUtils';
-import { isValidUrl, urlToRegex } from '../../common/urlUtils';
+import { isValidUrlWithProtocol, urlToRegex } from '../../common/urlUtils';
 import { PathMapping } from '../../configuration';
 import { ISourcePathResolverOptions, SourcePathResolverBase } from '../sourcePathResolver';
 
@@ -205,7 +205,7 @@ export class BrowserSourcePathResolver extends SourcePathResolverBase<IOptions>
         defaultPathMappingResolver,
         this.logger,
       );
-      if (isValidUrl(computedSourceRoot)) {
+      if (isValidUrlWithProtocol(computedSourceRoot)) {
         return new URL(url, computedSourceRoot).href;
       }
       return properResolve(computedSourceRoot, url);