For nothing. Absolutely nothing.
If they could be used to switch users or in any other way actually containerize desktop sessions, they could be useful for something.
I'd also go for "completely disabled".
I use to split personal and work stuff.
Mostly just change desktop wallpaper, have different pinned apps, and have some apps forced to start on specific activity using kwin rules.
And I sometimes also on top of that use workspaces, for additional split if different set of work/personal activities like switching between projects or leaving chat on one and IDE on another.
So it's almost like a simple 2x2 workspace grid but with additional window/taskbar rules.
I did something similar, although i gave up on it after a while
Now i use the virtual desktops, although typically, i put separate projects in each
If can be bothered
I have one for when I'm doing a presentation that customised for zero interruptions. The other is for everything else.
I use them instead of virtual desktops - each with a specific hotkey, and some with customized pinned apps.
I have ...
General: Email, shopping, etc.
Gaming
Media
Two Work activities - a primary, and a secondary for when I need to compartmentalize different ongoing tasks
Other - for anything transitory that doesn't fit in the others.
I realize this could largely be done with virtual desktops, though I don't think you can have a different pinned app loadout for each?
The downside to setting things up this way is when I restart my computer, it seems to randomly decide which browser windows go in each activity. Also, with apps that I use across them (like Notion), I have to go hunting for which activity it opened in. To get around the issue of splitting Firefox across different profiles, I just use two browsers. Firefox for work, and Firedragon for personal stuff. They share the same external password manager, so it's pretty seamless.
An easy one is "Personal" and "Work." I havent figured out how to combine it with Firefox profiles yet, but basically: instead of having to have two entirely separate user accounts, you can have Activities instead, and can hot-toggle between them.
I would want personal and work separated as users, though. Work requires proprietary tools I don't want to give read access to my personal files. And not being able to hot-toggle between them is a feature.
School and personal then. Or gaming and general. Or combinations of them. If you do hobby programming, you could have "dev" as one.
I mentioned this in my own top-level comment, but I just use different browsers for work and personal. Firefox for work, and my distro's fork for personal. That keeps those nicely separate.
I switch between Main, Recording, and Gaming. Apart from backgrounds I have some apps specifically visible in that Activity, and also have a filtered desktop folder for each (each Activity has files that are only relevant to that activity). I did a video about my switching at https://www.youtube.com/watch?v=wq-7KEeH7_U and how it differs from virtual desktops.
I have a bit of an unusual workflow, making use of 40+ workspaces, so I use Activities basically like meta-workspaces.
You have my curiosity, I wanna know your workflow.
Right, so it all started when I tried bspwm a few years ago and noticed that it didn't have a feature to minimize/hide windows. So, I looked up what that was about and one of the devs said that you shouldn't minimize, just move the window to a different workspace.
And yeah, that broke my brain. Because it's also a tiling window manager and I was on a small laptop screen, so only 3 windows would fit on a workspace at most.
But after using it for a while, I noticed that:
And yeah, eventually I tried replicating this workflow in KDE, because it has the workspace pager for my minimap (I have my workspaces in a column, so they fit onto the panel).
And so I found a KWin script to do the tiling (currently using Polonium), and realized that Activities are really useful for splitting up completely unrelated windows, too.
Recording meetings with other people, messing up with desktop layouts and whatnot.
But they haven't been pushed at all lately, and there were deprecation talks in the KDE forums.
In the past I used it together with KTimeTracker. It's a solution, of the many available... Sadly, none was really optimal IMHO
Are they like focus on iOS and macOS?
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