Adblock Plus can be installed on outdated/unsupported Opera versions

[Ross]

How to reproduce

Install Adblock Plus on Opera <36

Observed behaviour

Adblock Plus is successfully installed, but doesn't work properly, since it requires Chromium 49 (which corresponds to Opera 36) or higher.

Expected behaviour

Users on Opera <36 should not get the current version of Adblock Plus (through installation or update).

Once #5012 has been implemented, this can be achieved by updating the buildtoolsdependency and adding opera = 36.0 to the compat section in metadata.chrome.

[Ross]

Noticed when testing #4722. Since Opera is now based off Chrome maybe Opera needs a minimum version bump too? (Guessing).

[kzar]

I'm not sure how the minimum version required for Opera is defined since there's no longer a separate metadata file for Opera. (I'm also not sure what the minimum supported version of Opera should be.) Any idea Sebastian?

[kzar]

Looking at ​http://www.opera.com/docs/history/ it seems that Opera 36 corresponds with Chromium 49. This explains why earlier versions aren't working, they're just not supported.

[sebastian]

It seems we have to add ​minimum_opera_version to manifest.json in order to prevent installation on outdated/unsupported Opera versions. Having a uniform manifest.json for Chrome and Opera, shouldn't be a problem. Chrome will just pick up minimum_chrome_version, ignoring minimum_opera_version, and vice-versa does Opera.

[abpbot]

A commit referencing this issue has landed:
​Issue 4787 - Add compat value for minimum opera version

[Ross]

I could still install 1.13.1749 from the devbuild listing and from the Opera extensions store (1.13.1). I'm not sure if this worked or I'm testing it too soon? (I think the commit is in the devbuild by now according to the changelist?).

ABP 1.13.1749
Opera 35 / Windows 10

[sebastian]

The development build as of version 1.13.1.1794, includes the minimum_opera_version manifest entry that should prevent installation on Opera <=35. However, the release version (1.12.1), currently available from Opera add-ons, does not. From the top of my head, I can think of two possible reasons, if you can still install the development build on Opera 35:

1. Opera 35 might not yet support minimum_opera_version. In that case the changes here would be useless (until we increase the minimum requirements beyond an Opera version that supports it).
2. The minimum_opera_version key is not handled by the Opera browser, but by the Opera add-ons server-side infrastructure, and therefore it doesn't have any effect on the development builds.

[Ross]

I thought either of those might be the case. I couldn't readily find much information about when minimum_opera_version was implemented so I guess the best case is to recheck this as soon as it's updated on the store?

[sebastian]

Yeah, I couldn't find any information on how minimum_opera_version is supposed to work either (though it seems other extensions were already using it even before Opera 35). Neither could I find information on how exactly minimum_chrome_version limits installation on Chrome, in case it works the same way. So unless somebody figures something out that we missed so far, I guess we have to just release this change (assuming it didn't break anything), and have another look afterwards.