Can’t answer the rest of it, but copy and paste works anywhere there’s a standard text field unless the developer has gone to the trouble of disabling it. There

Can’t answer the rest of it, but copy and paste works anywhere there’s a standard text field unless the developer has gone to the trouble of disabling it. There are ways to make it work in non-standard text fields as well. You should send bug reports to the developers of the apps where it’s not working, same as you would if it didn’t work in macOS apps.