Fix error property propagation from background pages

[felixfbecker]

Currently, errors that go through the background-content-page boundary lose their error name: mozilla/webextension-polyfill#210. This means we need to use hacky string message assertion and cannot include any other context.
This has caused multiple bugs (e.g. #9411, #7599, ...) and many hours of engineering time lost.

names could always be propagated, custom properties are a bit more tricky because they may not be cloneable.

• Fix in comlink: @felixfbecker
• Fix in webextension-polyfill: @lguychard has a branch to fix this

[uwedeportivo]

Dear all,

This is your release captain speaking. 🚂🚂🚂

Branch cut for the 3.16 release is scheduled for tomorrow.

Is this issue / PR going to make it in time? Please change the milestone accordingly.
When in doubt, reach out!

Thank you

[uwedeportivo]

Dear all,

This is your release captain speaking. 🚂🚂🚂

Branch cut for the 3.17 release is scheduled for tomorrow.

Is this issue / PR going to make it in time? Please change the milestone accordingly.
When in doubt, reach out!

Thank you

[github-actions]

Heads up @Joelkw @felixfbecker - the "team/extensibility" label was applied to this issue.

[vdavid]

This is probably still an issue and would improve our tooling if fixed.