>>>>> On Thu, 26 Mar 2020 12:29:39 +0300, Ignat Insarov <kindaro@gmail.com> said:

    Ignat> When I type `⊢` (Unicode right tack, also called «turnstile»), the left
    Ignat> tack symbol appears instead. I can insert the turnstile with other
    Ignat> methods without problem.

Hi, this issue has been fixed already in emacs-27, under
bug#37530. You can try out emacs-27, or if you want to stick to
emacs-26 you can apply the patch from the bugfix to your local emacs.

Here it is: