You can check this with the team, I just had a quick look at the sample project shared by Quentin.
It looks like prerendering is done by loading the page in an headless browser, waiting for code execution and saving the result to disk, so I think your code gets executed.
Again, it’s only a wild guess, I’m sure the weweb team has the right answer for this.
Don’t you have the source code of the app if you are on the right plan? (Is there a sample project with Vue.JS exported code for review? - #4 by Quentin)