Keyboard gets cursor back in Facebook comment editor

Hello,

I have got some very strange problem (if I can say like that): When I start to type comment in Facebook, after the first letter written, cursor gets back (left from the first letter), and then writing continues the way the first written letter is right from cursor and always “goes” after cursor. Comment written stays without that first-written letter, which is last, instead to be the first. It is happening in Firefox Mozilla, not in Google chrome (I don’t use other browsers).

Example:

If I wanted to type LEAP it would be written EAPL

and cursor will continue to go before L

I hope that I explained this the way you understood. English is not my native language.

My Mozilla version is 78.13.0esr (64-bit) Running Leap 15.3 Keyboard is “Tesoro” (nothing more specific about keyboard I can not say).

What to do?

Thank you for answering my questions.

Hello, again,

Today “arrived” new versaion of Firefox (91.2.0esr (64-bit)) and now problem disappeared.