Multiple manifest.json to support Manifest v2 and v3 at the same time

[pbek]

Since Chrome is now forcing you to use manifest v3 and there still is a difference in the config for Chrome and Firefox (e.g. background scripts), is there a way to have two manifest.json files or to use some special mechanic to have different manifests for Chrome and Firefox?

I currently did something like:
https://github.com/qownnotes/web-companion/blob/5c8ebc2bcdf193556a4eaabd9cfb46aa89dbb773/app/manifest.json#L15-L23

But that is a feature of webextension-toolbox.

[pbek]

I currently help myself with just keeping two manifest files:

https://github.com/qownnotes/web-companion/blob/8f668be7d64153ffef664fcdf8d1fdc5bb2af4fe/package.json#L12-L19

Because even if you (like I did) use Manifest version v3 for Firefox and Chrome, there are lots of differences in the Manifest file. At least I managed to use the same JS in Firefox and Chrome in the end (was a hard struggle).