Are there any plans to implement a "Show Desktop" button? I find that a very useful function of the "TaskBar" extension (https://github.com/zpydr/gnome-shell-extension-taskbar), and would love to see that available in dash-to-panel.
Yes, I would like to add this feature. Some input on where/how it should be presented would be welcome. I was personally hoping to see it appear in a more condensed manner than taking up a whole application icon spot.
For "show desktop" im using custom hot corner extension. https://extensions.gnome.org/extension/1037/customcorner/
How about as a right-click on the "Show Applications" icon? I know bupkiss about JS, but presumably the icon area is listening for left-clicks. How difficult would it be to have it listen for right-clicks or middle-clicks and then minimize all the active windows to the panel?
Since only applications icons are shown, there is enough place for it on the panel and it won't hurt to add "one more" icon. May be right to application launcher.
Maybe Windows can be some inspiration with its hot bottom-left corner, which is also a button at the same time.
I ended up going with the windows-style thin button on the right side for now. Down the road we could add different type of styles or icons but the minimize/restore functionality is in there at least. It can be turned on/off in the settings. Here's a pic:

It does hides all the windows and shows desktop... including desktop icons as well :D Yes, that is a bug.
I thought you just wanted to look at your pretty wallpaper :)
Give it a shot now.
Works \o/
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I ended up going with the windows-style thin button on the right side for now. Down the road we could add different type of styles or icons but the minimize/restore functionality is in there at least. It can be turned on/off in the settings. Here's a pic: