Sticking with the workspace-per-project scenario:

What if there's no room in the workspaces that need Gimp? Or what if you only want Gimp occasionally, so you don't want it to fight for layout with your important windows in each workspace.

The downside of scratchpad is that you'll have many Gimps there, and they're disconnected from their related workspaces.

> Niri takes away the question of where to place it, but it definitely doesn't help with "Where the fuck is that one window I opened and how do I find it?"

In the workspace per project example, it's "my project foo Gimp is in the project foo workspace's overflow".

With something like i3/sway, you'll probably hide gimp in a tabbed/stacked container in some node in the workspace tree, but that's fiddly and kind of a hack in this example.

As for "where the heck is this window at all", I like mod-tab to MRU enumerate windows globally. This is a nice solution in any WM/DE.

> If you really need THAT much overspill on a workspace

We're just talking about an extra window here in a multi project setup which is something I run into dozens of times a day. You'll find a reference to this in every "I switched from i3/sway to niri" blog post. https://ersei.net/en/blog/niri - I'd say it's the main trade-off.

> Sure, Niri takes away the question of where to place it

We can probably just end it here, because that's the utility of a scrolling WM and you saw my point.