PSPad randomly replaced a line with Chinese hieroglyphs

It happened with PSPad v5.0.6 32b (used it for about a month or two without issues on the same JS file).
Last version I was using before v5.0.6: v5.0.3 32b (I think).

File: UTF-8 JS file.

Line before bug:
});

If I try to copy/paste that bugged line I get this:
᭠ͭ;

But this is what I see in PSPad (and other text editors) [5997]:

What I was doing:
Opened a JS file > added one line of code > saved to test JS -> no bug.
Copy pasted that line to other location > saved to test JS -> no bug.
Pasted that line to other location > saved to test JS -> bug appeared.

All edits were not near that bugged "5997" line.

Use 5.0.7 from developer forum.

It happened again with v5.0.7

Same (but at another line):
});

Randomly changed to:
ÿ

I've run into this, too, using 5.0.7 (731).
I've checked one occurrence of this in the hex editor view. The original byte sequence looked like
75 6C 6C 70 74 72 3B 0A 20 20 20 20 7D 0A 20 20, and it turned into
75 6C 6C 70 74 72 3B 0A FF 00 20 20 10 0A 20 20.

Likewise, that line was nowhere near any edits of mine.

Edited 1 time(s). Last edit at 2022-05-01 21:20 by buttercookie42.

just for clarification - this case is about files directly opened from FTP, right?

--
Vany
(PSPad 5.5.1.812 x32, W10h/p x64 en/cs)

Not in my case, no. They're regular files (mostly *.cpp files, though whether that has any bearing on the issue, or is just a coincidence because these last few days I've been busy backporting patches in C++ code) opened from my local drive.

This issue also just reoccurred while editing a different file, and interestingly it was the same change, i.e. from "20 20 20 20 7D 0A" to "FF 00 20 20 10 0A".

Edited 1 time(s). Last edit at 2022-05-05 21:57 by buttercookie42.

It seems that an alternative occurrence that has now happened a few times on different occasions in different files is turning
76 6F 69 64 0A ("void\n") into
FF 00 69 64 0A