Is there a typo in the Russian transliteration table?

Triaged as part of BSI today, we'll need to confirm the bug with someone that can speak Russian.

ц => ts
For example царь => tsar

That's about difference between Ш and Щ

Used to grep and a bit disappointed as both are valid but maybe not aligned with ICU

core/lib$ git grep "'shch'"
Drupal/Component/Transliteration/data/uk.php:21:  0x449 => 'shch',

is correct for Ukraine

core/lib$ git grep "'sch'"
Drupal/Component/Transliteration/data/kg.php:21:  0x449 => 'sch',
Drupal/Component/Transliteration/data/x04.php:13:  0x40 => 'r', 's', 't', 'u', 'f', 'kh', 'c', 'ch', 'sh', 'sch', '', 'y', '', 'e', 'yu', 'ya',

so both letters are covered 'sh', 'sch' for Russian but as comment #6 already said it's preferable to continue use it - both ts and sch https://en.wikipedia.org/wiki/GOST_7.79-2000

#3169212: Improve transliteration of Ukrainian letters → also has some discussion on this.

So ultimately what is the path forward for this one?

Since it's been about a month wonder what the path forward is for this one? Anything can be changed or no matter what is one approach wrong.

As @andypost mentioned in #7, the issue is about 2 variants of transcribing "щ" character that are found in the core.
From several sources I've checked, "shch" variant is more "favourable", so I'd suggest use it consistently in all places

Let's use ICU variant - shsh as the summary states

Agreed; shch should be used.

I almost made the branch name 3215368-щ but then no one would have been able to type it.

(Of course, there's the whole thing where in Bulgarian it makes almost a "th" sound as I learned during Dev Days last year, but what can you do.)