This is an old issue when production grade build is used.
You are probably using Vue from CDN, and probably using a production build (dist/vue.min.js). Either replace it with a dev build (dist/vue.js) or add Vue.config.devtools = true to the main js file.
This is an old issue when production grade build is used.
Check out the github
link
.But, for me, the problem with DevTools was solved just when I put the line that is provided in the answer below after creating your Vue application.
Your code should look like this
Be sure you have this setting in your app.js file
If you are using mix, check the dist of vue in webpack.mix, be sure you don't use min version
Run your npm in dev
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