User Agent: Mozilla/5.0 (X11; Linux x86_64; rv:91.0) Gecko/20100101 Firefox/91.0

Steps to reproduce:

I tried search for name Modes in 91.5.0 (64-bit)

Actual results:

I got a bunch of mails containing the word modely, módě, mode. Thats the googles way to break the searches. Thunderbird was cool because it did not try to play smart and it did what I requested while at the same time gmail and google was searching for anything somewhat related and usually completely irrelevant to my search. Now I see this "improvement" was incorporated into thunderbird.

Expected results:

It should have returned only mails containing the name Modes and also mails mentioning the word modes. At least if it was put in quotes for gods sake!

I use thunderbird since the very beginning because its was fast (no longer true since the whole thing is in javascript instead compiled from something) and I use it still because it had a wonderful search that always found all what I requested and nothing I did not. Now its as botched as gmail and its either a bug for a quick fix or I will have to install thunderbird version 2 which was pretty stable, reliable, fast... Probability of any scam targeting againts that version is very small.

Assuming you are using global search field, this isn't changing any time soon.