<h3 dir="auto">Version</h3>
<p dir="auto">2.6.10</p>
<h3 dir="auto">Reproduction link</h3>
<p dir="auto"><a href="https://test.ipalfish.com/klian/web/dist/m/picture/vip-code.html?from=singlemessage&amp;isappinstalled=0" rel="nofollow">https://test.ipalfish.com/klian/web/dist/m/picture/vip-code.html?from=singlemessage&amp;isappinstalled=0</a></p>
<h3 dir="auto">Steps to reproduce</h3>
<p dir="auto">config project by vue-cli 3.0,  then load page in wechat devtools</p>
<p dir="auto">see the error below:</p>
<p dir="auto">libs.213765e4.js:1 Uncaught SyntaxError: Invalid regular expression: /[^a-zA-ZÂ·Ã€-Ã–Ã˜-Ã¶Ã¸-Í½Í¿-á¿¿â€Œ-â€�â€¿-â�€â�°-â†�â°€-â¿¯ã€�-íŸ¿ï¤€-ï·�ï·°-ï¿½.$_\d]/: Range out of order in character class<br>
at RegExp ()<br>
at Module. (libs.213765e4.js:1)<br>
at Module.2b0e (libs.213765e4.js:1)<br>
at r (vip-code.f5f61c2a.js:1)<br>
at Object.a1c6 (vip-code.f5f61c2a.js:1)<br>
at r (vip-code.f5f61c2a.js:1)<br>
at Module.56d7 (vip-code.f5f61c2a.js:1)<br>
at r (vip-code.f5f61c2a.js:1)<br>
at Object.17 (vip-code.f5f61c2a.js:1)<br>
at r (vip-code.f5f61c2a.js:1)</p>
<h3 dir="auto">What is expected?</h3>
<p dir="auto">render successfully</p>
<h3 dir="auto">What is actually happening?</h3>
<p dir="auto">report an error</p>
<hr>
<p dir="auto">it seem to a bug in vue.esm.js line 478<br>
var unicodeLetters = 'a-zA-Z\u00B7\u00C0-\u00D6\u00D8-\u00F6\u00F8-\u037D\u037F-\u1FFF\u200C-\u200D\u203F-\u2040\u2070-\u218F\u2C00-\u2FEF\u3001-\uD7FF\uF900-\uFDCF\uFDF0-<br>
it only happen when production<br>
<code class="notranslate">config.devtool = isDev ? 'cheap-module-eval-source-map' : 'hidden-source-map'</code></p>
<p dir="auto">in my component,i use some custom element just for making it won't be effected by other style.<br>
such as:</p>
<div class="snippet-clipboard-content notranslate position-relative overflow-auto" data-snippet-clipboard-copy-content="&lt;template&gt;
  &lt;!--'my-el' is just a common dom el,not component--&gt;
  &lt;my-el&gt;&lt;/my-el&gt;
&lt;/template&gt;"><pre class="notranslate"><code class="notranslate">&lt;template&gt;
  &lt;!--'my-el' is just a common dom el,not component--&gt;
  &lt;my-el&gt;&lt;/my-el&gt;
&lt;/template&gt;
</code></pre></div>
<p dir="auto">but,vue always warm that ''Unknown custom element...',how to ignore it without runing '<code class="notranslate">Vue.config.silent = true</code>'?</p>