This issue has a similar reason to T208139, but it's distinct.
The Georgian alphabet has problematic rules with automatic capitalization. Various pieces of software handle capitalization of this alphabet in unexpected ways.
Because of this, adding links in Visual Editor doesn't work as it should.
- Create a page in ka.wikipedia.org (Georgian Wikipedia).
- Edit the page in VE.
- Write the text თბილისი (this is the name "Tbilisi", capital of Georgia).
- Select this whole word and add a link using it.
- Click the first autocompletion suggestion.
- Click "რედაქტირება" (Done).
Expected result: Blue link pointing to the article თბილისი.
Actual result: Red link.
The reason is that at some point, the first letter is auto-capitalized. Depending on the device that you are using, it either appear the same as "თბილისი", or the first letter may appear as a square.
This autocapitalization must not be applied here.