Bad rule with nested uBO modifier ':matches-media(...)'

[105th]

Prerequisites

• This problem is not related to filtering issues. Otherwise, you should read this article;
• You're using an up-to-date version of the problematic filter;

Problem description

During converting filters we noticed error:

failed to process rule: '[$path=/^((?!^/$).)*$/]dawn.fi#$#.header:not(:matches-media((min-width: 750px))) + div[class] + div[class] .mobile-top-ad { margin: -10px auto !important }' due to: uBO modifier ':matches-media(...)' cannot be nested
Stack trace:
AdblockSyntaxError: uBO modifier ':matches-media(...)' cannot be nested

Problematic rule is in the filter 233 -

FiltersRegistry/platforms/extension/chromium-mv3/filters/233.txt

Line 22 in 316be41

[$path=/^((?!^/$).)*$/]dawn.fi#$#.header:not(:matches-media((min-width: 750px))) + div[class] + div[class] .mobile-top-ad { margin: -10px auto !important }

Proposed solution

Fix rule please :)

Privacy

• I agree to follow this condition

[piquark6046]

The filter exists in a third-party filters list that AdGuard filters devs cannot modify directly.

[105th]

@piquark6046 so i should fill the issue inside this filter's repository?

[piquark6046]

We can open an issue to fix this issue at https://github.com/finnish-easylist-addition/finnish-easylist-addition/issues.
And, AdGuard should support uBlockOrigin/uBlock-issues#2185 for any filter using the syntax.

[105th]

Okay, filled there - finnish-easylist-addition/finnish-easylist-addition#465, thank you

[peace2000]

I can check if the filter is still relevant and if there are workaround options for it, but shouldn't this syntax be valid for Adguard in the first place?

[105th]

@peace2000 if i understood docs correctly (https://github.com/uBlockOrigin/uBlock-issues/wiki/Procedural-cosmetic-filters#subjectmatches-mediaarg), the issue here is not about AdGuard lacking support, but rather a syntax limitation in uBO's procedural cosmetics.

:matches-media(...) can be part of a chain (e.g. .class:matches-media(...)) but cannot be nested.

Also i have not found any examples on whole github with :not(:matches-media()), but i'm not familiar with blocking rules themself, so please correct me, if i wrong.

[peace2000]

https://github.com/uBlockOrigin/uBlock-issues/wiki/Procedural-cosmetic-filters#subjectnotarg

Nesting any procedural cosmetic filter inside :not() is a valid way to negate other procedural filters in uBO.

[krystian3w]

If improving the conversion at AdGuard side is unattainable (something similar to my suggestion like rule number 2), it may be possible to change it to:

dawn.fi##:matches-path(/^((?!^/$).)*$/):matches-media((max-width: 749px)) .header:style(property: value)
! or
dawn.fi##:matches-path(/^((?!^/$).)*$/):matches-media(not (min-width: 750px)) .header:style(property: value)

The downside is that you have to subtract a pixel and the pseudo pixels will not be captured (zoom can take "fractional" pixels, e.g. 749.5px) in max-width scenario (first suggestion).

As if the Finnish list removed the filter (I see a filter and that the uBo txt file variant hasn't had any improvements for 2 months), the comment can serve as a workaround for other lists.

The second variant run as native CSS in uBo, the add-on does not have to dynamically add a random attribute as in the procedural version due change window width.