Your PSPad version? Tested in 5.0.7 and it behaves correctly

Background: I need clear window titles for automatic detection of open script
files.

I don't understand, but in the scripting you have access to all open files, open
files count e.t.c.

You can open several PSPad instances with same file. When file is changed and
saved and you switch to another instance, PSPad informs you.

Several instances:
1. disable one instance in the Program settings / System integration
2. open new instance even one is running:
 -N or /N parameter with PSPad start
 
>From the right menu on the file tab you can open file in New instance

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<https://forum.pspad.com/read.php?2,77220,77221>
PSPad freeware editor https://www.pspad.com

Odpovedet emailem