Copy&Paste in Firefox

[m-mohr]

Firefox doesn't support accessing the clipboard as we use it right now:

Firefox only supports reading the clipboard in browser extensions, using the "clipboardRead" extension permission.

We can circumvent this for the model builder by just using an internal store for copy&paste within the app. Doesn't allow pasting from external sources, but that's rarely used anyway.

Source: https://developer.mozilla.org/en-US/docs/Web/API/Clipboard/readText