For a long time, panel at the bottom of my screen (like a "dock") for Plasma has been starting with all the contents compressed into a single small square. That's been easy to restore back to its normal size, with "Show panel configuration" in the context menu, but it was annoying. With today's sync, apparently KDE finally got it right. It now starts out with its normal size, no workarounds needed!
EDIT: Aw, fsck! The above seems to apply to my laptop only. When I updated my wife's and restarted it, the dock remained compressed into small square with its three contents squeezed to incredibly tiny icons. Since both laptops are identical DELL Latitudes, and both are running Solus Plasma, both fully updated, I'm not sure why that issue seems to be fixed on mine and not on hers. Again, easily worked around, but annoying nonetheless.
MORE EDIT: After thinking about it for a while, I believe I've found the difference. Because of all the X11 vs. Wayland discussion on the forum lately, when I restarted my laptop after updating it this morning, I was curious and first launched an X11 session. Indeed, the "dock" opened to its normal size and contents. Then I rebooted and launched my usual Wayland session, and it too opened to its normal size and contents. That's why I wrote the first message above. However, I didn't open an X11 session on my wife's laptop, but just started Wayland after a reboot, and as I noted, the dock issue was still present.
I had forgotten that I restarted the two laptops differently this time. Apparently X11's being started first made it so that Wayland also started up correctly. I hate mysteries.