POC / Support old browsers by using @vitejs/plugin-legacy

[langemike]

This change will make the site work on older browsers.

Build instructions:

cd platforms/web
APP_DEFAULT_CONFIG_SOURCE=gnnuzabk LEGACY_DEBUG=true  yarn build
yarn vite preview --host

Now visit the URL in your old browser.

Unfortunately, you will need to rebuild the app on every change since it is not possible to inject polyfills/transforms on-the-fly on a dev server.

I ran into an issue where Chromium 68 should load the "legacy" version based on a browser feature detection algorithm within plugin-legacy (see source). But it didn't.

Therefore I introduced the LEGACY_DEBUG flag to enforce loading the polyfills. I can give a detailed explanation about this endeavor if needed (it goes in to the specifics of chromium) ;) This is what I finally ended up with. I think this makes development easier, as we can locally install Chromium instead of being dependent of an external browser.

LEGACY_DEBUG is a temporary solution that I do not want to commit into the code.

I still need to find some kind of way to combine @vitejs/plugin-legacy with vite-plugin-html because currently I discarded the latter, because the first takes care of the logic of deciding in loading the modern vs. legacy bundle.

Ticket: https://videodock.atlassian.net/browse/OTT-1130

[langemike]

You may have a look at the basis of supporting old browsers. Tomorrow after the daily I can tell you how I would like to move forward @ChristiaanScheermeijer @MelissaDTH @royschut

Feedback is already welcome.

[langemike]

Transformed POC in to a proposal: #182