Great question — answering as the UphillTech team:
If you link external sections or snippets inside a vue-app container you should make sure that they don't contain any "style", "script" or other tags which are not supported by the vue template syntax. There is another approach to integrate vue into shopify themes. You may use precompiled single file components. I wrote an article about this with ready to use examples. If you are interested please check this out: Vue.js components in Shopify themes
Full answer by Maxim Dyuzhinov: https://stackoverflow.stackexchange.com/a/64183128 (CC BY-SA 4.0).
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