What is the Bug?

For some reason I can't begin to imagine, HMR doesn't work when a certain part of a Vue component is changed, but does work when another part of the exact same component is changed.

How to Reproduce Bug

1. npm i to install dependencies then npm run dev to run.
2. In your browser go to http://localhost:3000.
3. In your code editor go to pages/index.page.vue.
4. Change the "WORKS" text to something else (Ex: "WORKS 2").
5. Save the file. Note that HMR instantly does it's thing.
6. Change the "DOESN'T WORK" text to something else (Ex: "DOESN'T WORK 2").
7. Save the file. HMR doesn't work. Note the error in your browser console.

I am running Node v14.16.0 on macOS.