Timeless skin for Arch (take 2)

Created by: lahwaacz

This extends https://github.com/archlinux/archwiki/pull/50 with more tweaks for current MediaWiki 1.40. From my side it is finished, except for the inconsistencies in responsive behavior (see https://github.com/archlinux/archwiki/pull/50#issuecomment-1368253236) which I will try to address separately.

I believe that modifications for this skin will be easier to maintain than for the "new" Vector which breaks with every new major MediaWiki version. I think we can remove our modifications for Monobook though, which is old and ugly. Maybe we can even make Timeless the default.

This is what the Timeless skin looks like:

1. 1400 x 800
2. 1100 x 800
3. 1000 x 800
4. 800 x 800
5. 300 x 800

/cc @progandy @pierre @gromit @archlinux/teams/wiki/admins

changed title from Draft: Timeless skin for Arch (take 2) to Timeless skin for Arch (take 2)

Created by: nl6720

/cc @slokhorst @fengchao

restored source branch github/fork/lahwaacz/timeless

changed the description

requested review from @progandy

changed the description

added scopefeature label

This has not received any objection since I submitted the merge request (originally on GitHub), so I think we can leave last 2 weeks for discussion and then proceed with the merge

requested review from @pierre, @nl6720, @lahwaacz, @alad, @lonaowna, @kynikos, @netsysfire, @kewl, @det87, @skydiver, @flyingpig, @gordian.edenhofer, @erus_iluvatar, @indigo, @fengchao, @andreymal, and @codingkoopa

added 26 commits

• 5ad3fa43...f3e45789 - 18 commits from branch master
• 60ea99cd - Add Timeless skin support in ArchLinux extension
• a76e2bb9 - Timeless skin tweaks
• b9c0b8b3 - Hide logo text in the Timeless skin
• 2b5ca668 - Fix positioning of extra navigation from Extension:Echo in the Timeless skin
• c20f6295 - Improve layout of navigation menus in the Timeless skin
• c75ce390 - Disable background image in the Timeless skin
• 09beb248 - Fix body background in dark mode in Timeless skin
• 9b86808e - Reset hardcoded white-on-blue colors in the Timeless skin

Compare with previous version

assigned to @lahwaacz

added 10 commits

• 9b86808e...b83fe432 - 2 commits from branch master
• 495ade3c - Add Timeless skin support in ArchLinux extension
• f48dfa14 - Timeless skin tweaks
• 2f20abb8 - Hide logo text in the Timeless skin
• a3de65df - Fix positioning of extra navigation from Extension:Echo in the Timeless skin
• 7ccfad02 - Improve layout of navigation menus in the Timeless skin
• 1a154cbe - Disable background image in the Timeless skin
• 16c28b87 - Fix body background in dark mode in Timeless skin
• f036e269 - Reset hardcoded white-on-blue colors in the Timeless skin

Compare with previous version

mentioned in commit 2ac7fdb8

merged

mentioned in merge request !50 (closed)

mentioned in commit lahwaacz/infrastructure@ad409d55

mentioned in commit lahwaacz/infrastructure@124db3a6

mentioned in merge request infrastructure!817 (merged)