Weird chars appear unexpectedly in text files .... (solved!)

[cobaka]

Hello all & woof!

Weird things are happening on my desktop puppy.

The immediate context: I have a makefile open, (in Geany, of course).
Taking a break I went looking at photos of Maatsuyker Island - and I visited several pages on the web - photos of places etc.
Then I read a little more about "make" and re-directing IO before I returned to Geany.
Here is a snapshot. You can see it's a "make file" - but whoa!! I see additional text inserted into the file!

weird_chars_in_file.jpg (40.64 KiB) Viewed 582 times

You can see it: https: etc
At the end you see the original line in the make file began: CFLAGS = (and so on).
And (yes!) web address is one of the photos/pages I visited. Nice photo eh?

This is a 'several times' experience. I had the same thing (additional text) in an open-document file. (LibreOffice 5.3)
Can anyone suggest what's going on here? Am I doing something wrong? Have I failed to attend Mass recently?

собака

howling.jpg (3.17 KiB) Viewed 580 times

[Burunduk]

Middle-click? I can't imagine what else it could be. Select text to copy, middle-click to paste. It may be a loose mouse wheel or a touchpad configuration. I've configured one of the touchpad corners to serve as a middle button and trigger it sometimes inadvertently. If your puppy has a working clipit program sitting in the system tray, you can click its icon to see your clipboard history. The web address appeared in geany should be there too.

[misko_2083]

^Vodka? A bit of computing under the influence, mhm, Цобака.
We caught you now ha, ha, ha.

[cobaka]

Водка? Немного вычислений под воздействием, м-м, вобака.
Мы поймали вас сейчас ха, ха, ха.

Да, @misko_2083 это правда! You caught me.
In Budapest vodka cost only $10.oo Here, in Australia, much more.

I forgot to mention my Puppy. uPupBB32

Thinking about other postings. @Burunduk
I don't know if I have a three button mouse. There isn't an obvious 3rd button, but maybe it's tied to the mouse wheel.
When I depress the wheel, I hear 'click'. [a short delay ... then] Oh, oh, oh! I just did an important scientific experiment! When I copy text and press the wheel - then the text in the 'copy buffer' - I just invented a thing called 'copy buffer' - appears/is pasted! So - I think your suggestion is correct in outline. Now I must discover the detail!! I think this one is solved!

Thank you!

собака