<h1 dir="auto">Bug report</h1>




<p dir="auto"><strong>What is the current behavior?</strong><br>
when debuging an vuejs project with firefox , the genereate source map is not dispalyed correctly. on chrome it is Ok</p>
<p dir="auto">i have two generated bundle: <code class="notranslate">main.js</code> <code class="notranslate">chunk-verndor.js</code> and two source map: <code class="notranslate">main.js.map</code>, <code class="notranslate">chunk-vendor.js.map</code></p>
<p dir="auto">this is the screen shot for firefox :<br>
<a target="_blank" rel="noopener noreferrer nofollow" href="https://user-images.githubusercontent.com/733502/89769802-b4992700-daf5-11ea-88d3-f0d9a8b0d32f.png"><img src="https://user-images.githubusercontent.com/733502/89769802-b4992700-daf5-11ea-88d3-f0d9a8b0d32f.png" alt="Screenshot from 2020-08-10 10-37-04" style="max-width: 100%;"></a><br>
the displayed text:<br>
<code class="notranslate">import mod from "-!../../node_modules/cache-loader/dist/cjs.js??ref--12-0!../../node_modules/thread-loader/dist/cjs.js!../../node_modules/babel-loader/lib/index.js!../../node_modules/cache-loader/dist/cjs.js??ref--0-0!../../node_modules/vue-loader/lib/index.js??vue-loader-options!./FileChart.vue?vue&amp;type=script&amp;lang=js&amp;"; export default mod; export * from "-!../../node_modules/cache-loader/dist/cjs.js??ref--12-0!../../node_modules/thread-loader/dist/cjs.js!../../node_modules/babel-loader/lib/index.js!../../node_modules/cache-loader/dist/cjs.js??ref--0-0!../../node_modules/vue-loader/lib/index.js??vue-loader-options!./FileChart.vue?vue&amp;type=script&amp;lang=js&amp;"</code></p>
<p dir="auto">this is the screenshot for chrome:<br>
<a target="_blank" rel="noopener noreferrer nofollow" href="https://user-images.githubusercontent.com/733502/89769896-e0b4a800-daf5-11ea-95ed-e0111693ea98.png"><img src="https://user-images.githubusercontent.com/733502/89769896-e0b4a800-daf5-11ea-95ed-e0111693ea98.png" alt="Screenshot from 2020-08-10 10-39-44" style="max-width: 100%;"></a></p>
<p dir="auto"><strong>If the current behavior is a bug, please provide the steps to reproduce.</strong><br>
build vuejs with source map</p>






<p dir="auto"><strong>What is the expected behavior?</strong><br>
firefox should display like chrome</p>


<p dir="auto"><strong>Other relevant information:</strong><br>
webpack version:  4.44.1<br>
Node.js version: v10.21.0<br>
Operating System: ubutun 20<br>
Additional tools: @vue/cli 4.4.6</p>
<p dir="auto">I've put together a quick repo to demonstrate the problem: <a href="https://github.com/Stuk/webpack-sourcemaps-firefox">https://github.com/Stuk/webpack-sourcemaps-firefox</a></p>
<p dir="auto">And here's a gif of the issue in action:</p>
<p dir="auto"><a target="_blank" rel="noopener noreferrer nofollow" href="https://cloud.githubusercontent.com/assets/48019/8346824/1b3e9ada-1ab7-11e5-8848-271aa7933b2c.gif"><img src="https://cloud.githubusercontent.com/assets/48019/8346824/1b3e9ada-1ab7-11e5-8848-271aa7933b2c.gif" alt="screencap" data-animated-image="" style="max-width: 100%;"></a></p>
<p dir="auto">I've checked Uglify, and Firefox has no issues there. I've tried the different config options for <code class="notranslate">devtool</code>:</p>
<ul dir="auto">
<li><code class="notranslate">eval</code> - works</li>
<li><code class="notranslate">cheap-eval-source-map</code> - works</li>
<li><code class="notranslate">cheap-source-map</code> - does not work</li>
<li><code class="notranslate">cheap-module-eval-source-map</code> - works</li>
<li><code class="notranslate">cheap-module-source-map</code> - does not work</li>
<li><code class="notranslate">eval-source-map</code> -  works</li>
<li><code class="notranslate">source-map</code> - does not work</li>
</ul>
<p dir="auto">So seems like eval is file, but an external sourcemap for multiple files does not.</p>
<p dir="auto">Any thoughts about what's going on?</p>
<p dir="auto">I've also filed an issue on Bugzilla, in case this is a FF devtools issue: <a href="https://bugzilla.mozilla.org/show_bug.cgi?id=1177329" rel="nofollow">https://bugzilla.mozilla.org/show_bug.cgi?id=1177329</a></p>