@Jamayka24 :-
I've used various iterations of radky's JWMDesk Manager for years. It's up to around v3.7/3.8.....somewhere like that, but my favourite version has always been v2.4.3.
Roger's stuff has always been very well thought-out & exquisitely executed, yet I found that from around v3.0 onwards, with all the new stuff that was being added, that it was beginning to get over-complicated.....and although this is in no way a criticism of Roger's work, it's been getting so that much of the newer stuff - for building/customizing themes, customizing the top window bar, adding different button themes AND a ton of other things - is no longer exactly intuitive. Not for me, at any rate.
There MAY well be a GUI method now for changing the tray icons to one's personal taste.....but I kinda got lost with a lot of the new stuff, and I just didn't bother digging that deep.
Myself, I've always modified the 'tray' manually, by directly editing /root/.jwmrc-tray (this is one of the 'hidden' files in /root), which you access by clicking on ROX's 'eye' icon in the Menu bar at the top of the window. You can change icons for any of the 'launcher' buttons immediately to the right of the Menu/Start button in the bottom left corner. Anything in the 'notification' area - over to the right, near the clock - those are all covered by ROX's 'swallow' function, which I've never really understood.....and I don't think you CAN change THOSE particular icons. There may be a way, but it would involve modifying the 'short' .desktop files in /root/.config/autostart; TBH, I've never bothered to modify these, and just leave them as they come.
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For modifying the 'quick launch' buttons on the left hand side, only three things are needed. A 'title' - which shows as a 'popup' when you hover over the button. An icon.....and the $PATH to your executable.
There's been a lot of discussion about suitable icons over the years; many maintain that to do things the correct way, you MUST use 16x16 icons down here.....and they HAVE to be in .xpm format. I've never bothered with all that. I always use PNG icons, because of the transparency layer these come with, and ranging in size anywhere from 128x128 up to 512x512.....and ROX-Filer will automatically resize icons to 16x16 for the tray OR 48x48 for the desktop 'pinboard', irrespective of the size you use.
I have a directory with an eclectic selection of nearly 900 assorted PNG icons that I've amassed over the years from hundreds of Google/DuckDuckGo searches, OR which I've actually created myself. I'm not a fan of 'themed' icon sets, despite that many here seem to love 'em; I would far sooner an icon showed me what it actually does, rather than some vague, generic 'stylistic' indication of what it MIGHT be for.
I also loathe the modern 'flat' icon fad. Eurrrgh! My favourite period of design was around late WinXP/early Vista, when icons had a '3D' effect, with sharp, clean lines, highlights/shadows, etc., and an icon immediately made it crystal clear what the button was supposed to do. And they LOOKED good!
But I digress.
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You can usually find something like what you want by doing a search for, say, "PNG icons for (whatever)" That's all I use. When you've found something you like & have downloaded it, you want to stick it in one of the image directories that are "in the $PATH"; these are standard locations where your Puppy will always look for icons by default. In theory, you then only need to use the name of the icon; you don't even need to add the ".jpg/.png/whatever" after it. I always use the full $PATH, so that there can be NO mistake.......despite that this is NOT the "Linux way"!
The most common ones are:-
There's also one at /usr/local/share/pixmaps, but very few apps or people tend to use this one. I'd bung 'em in /usr/share/pixmaps, if that was me; it's the most common location for 'one-off' icons by a mile.
And then all you do is to change the icon location in /root/.jwmrc-tray. Then, run
.....in the terminal, and Bob's yr uncle! you should now have changed your icon.
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That's how I approach this. But many will have different preferred approaches to mine.....
Mike.