@JohanV: - regarding your Q in the OP:
As an AHK user, I did a duckgo search for info on this: autohotkey - detect change in window
 - and some of the results looked potentially useful.
For example, including:

• Method to detect active window change?
• Run script on active window change

I also did a duckgo search on this: event viewer - detect change in a window
 - as I wondered whether that might be an easy avenue to pursue (anything that occurs in the system could probably be defined as an event).
Not sure whether the results would be useful though, as I know little about triggering/viewing system events, though I am aware that several third party applications "log" events to the viewer and subscriptions can also be enabled - e.g., for remote PCs or dual monitors. It seems to be a pretty sophisticated component of the OS.

Hope this helps or is of use.

NPC WARNING! The following post includes explicit language, mixed with social commentary and  dollops of irony and satire  - a Good Example of British humour in times of stress.
May seem difficult to understand if all one can see is politics.

17 Million F*ck Offs - A Song About Brexit.
Absolutely brilliant and cruelly accurate statement, all put to music by the author/singer/performer Dominic Frisby - a respected financial writer, libertarian and entertainer.



I originally saw this video linked from Guy Fawkes' Blog - https://order-order.com/2019/03/21/17-million-fk-os-2/
Apparently it was charting at No.1 on Amazon UK at 1 quid each.

As 1 reviewer put it:

With all the Brexit stress we needed some light relief and Dominic has done an admirable job with this comical account of Brexit set to the tune of the old English folk song "Widecombe Fair". Not too sure if there's any reason for using this particular song - is the "old grey mare" Brexit and the merry group of men the remain MPs?
He manages to feature most of the antagonists, names who you will know and now have a helpful way to remember them for later encounters. Bravo.

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The lyrics make good use of the well-known old folk song - Widecombe Fair - because it is an old favourite and lists lots of people/names/details, each chorus ending in"...and Uncle Tom Cobbly an' all, and Uncle Tom Cobbly an' all." - which phrase became part of the English language (as a colloquialism).

There's more humour though - this next one is a cleverly-done spoof by Remainers, cobbled together using words spoken by Brexiteer Jacob Ress-Mogg and put to music: https://twitter.com/PoliticsJOE_UK/status/1092740115716362241/video/1
I rather like it.
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