[Manifest V3] Broken error handling in background script

[Pharb]

Describe the bug
A clear and concise description of what the bug is.

To Reproduce
Steps to reproduce the behavior:

1. Go to any login page
2. Try to fill in password from gopassbridge
3. Use wrong GPG pin (or other error case preventing successful password retrieval)
4. See error in dev tools Uncaught (in promise) Error: browser.extension.getViews is not a function from processMessageAndCatch

Expected behavior
Error can be shown in notification if popup is closed.

Screenshots

System (please complete the following information):

• OS: macOS 14.7
• Browser: Chrome 129.0.6668.101
• Gopassbridge version: 2.0.0
• gopass --version: gopass 1.15.14 go1.22.5 darwin arm64
• gopass-jsonapi --version: gopass-jsonapi version 1.15.14

Issues with installation

• Did you try restarting your gpg-agent and browser (e.g. killall gpg-agent)? YES
• Did you reconfigure gopass-jsonapi with the current version (e.g. gopass-jsonapi configure)? NO

Did the problem change with these steps (e.g. different error message, now it works)?

YES, this usually fixes the problem, but the error handling is still incompatible running with Manifest V3 APIs.