Use match_origin_as_fallback behavior by default in scripting.executeScript

[oliverdunk]

In Manifest V2, the tabs.executeScript method has a matchAboutBlank property which matches the behavior of match_about_blank in the manifest.

In Manifest V3, the scripting.executeScript method in Chrome applies this behavior by default. We chose this since the API is more explicit about the injection target, and therefore there is clearer intent from the developer to inject into a given frame.

However, since then we have introduced match_origin_as_fallback. We'd like to make that the default for scripting.executeScript. This will need some communication, since it's technically a behavior change, but should be low impact.

[tophf]

MV3 executeScript uses kMatchForAboutSchemeAndClimbTree to mimic MV2 executeScript, I guess.

MV3 registerContentScripts uses kAlways and exposes matchOriginAsFallback explicitly.

Hence, maybe it would make more sense to expose matchOriginAsFallback for executeScript (both in MV3 and MV2) and use kAlways mode when it's true?

[Rob--W]

@kiaraarose Could you confirm Safari's behavior and set it to implemented: safari Implemented in Safari if applicable?

[oliverdunk]

I've filed a Chromium issue to track this work here: https://issues.chromium.org/363031548

[xeenon]

Safari will not inject into a frame if permissions are not granted, and currently permissions are only granted based on HTTP-family URL patterns. An about:blank, etc. frame targeted with frameId will fail the permission check today in Safari.

We are supportive of this issue and would implement it once we have match_origin_as_fallback support, since that nicely aligns with our permission model.

[Rob--W]

@kiaraarose Could you confirm Safari's behavior and set it to implemented: safari Implemented in Safari if applicable?

Kiara mentioned that Safari does currently not inject in about:blank, and that support for match_origin_as_fallback is planned to being worked on.

[Rob--W]

FYI: During TPAC 2024 (#659) I sat together with Oliver and he created a patch to implement this in Chromium: https://chromium-review.googlesource.com/c/chromium/src/+/5890628

Once that is approved and merged, the chrome label on this issue can be updated and the ticket be closed.