I upgraded from v12.26 last night to latest stable v12.28. Now the UI of the program is very laggy. I have 2 panes, top and bottom layout, with a LOT of tabs. When I was on v12.26 switching between the top and bottom panes were fast, almost instant. Now when I switch between them, there is a 2 second-ish delay, making the user experience feel very laggy.
The ONLY thing I changed was a new theme. But I have tried resetting to the plain default theme according to the pinned topic from the Themes section but it didn't help with the lagginess.
Is there any fix for this? Can I downgrade back to 12.26 by installing on top of the current installation?
A delay when changing which panel is active will usually be caused by one of two things:
Something in the toolbars which takes a long time to refresh.
Try resetting to the default toolbars to see if that's the case. (Settings > Toolbars > Factory Reset Toolbars.)
A script add-in.
Try removing all script add-ins, if any have been installed. (Preferences / Toolbars / Scripts)
(Of course, use Settings > Backup & Restore first, so you can easily revert any changes you make.)
Buttons, shortcuts, favorites or tabs which point to unavailable network drives can also cause slowdowns in unexpected places. If any of those exist, try removing them (or try when the machine they point to is available on the network).
My toolbars are 99% default, only things I changed were I moved the different view modes (list, detail, tiles etc) from the dropdown list onto the toolbar as buttons so less clicks when I change view mode. Nothing else applied, no scripts, network locations etc. But your suggestions made me remember I also changed the toolbar icons after the update but I didn't think it would matter so never thought about it. I changed it back to default icon set to test... and lo and behold the lag is gone right away!
I really don't understand, why would an icon set lag the UI that much? It's not like it's super high-res icons, after importing it it shows the same res as default 22x22, 32x32. The icon set I used is this: S-THEME Icon Set II (over 500 icons)
Thank you so much for the solution. Was getting very annoyed by the lag
edit: it occurred to me it says "500 icons" maybe that's why it lagged. but after I imported the icon set it showed around 100 icons in settings, not 500.
An iconset shouldn't normally slow things down, other than making startup take slightly longer. That's quite strange.
The iconset has got actually 181 32px icons and 181 22px icons, so around 400. It exists since 2016 and started with more icons, but some were removed, replaced or combined over the years. If you see 100, it's not my original set.
The are lots of people using this set (and other) over years now, never anyone had probs slowing DO down. I use it myself on 4 devices and on hundreds other via USB and also never had any problems.
BTW if the amount would slow down, the internal default set could never be used.
Looking at the icon set, I can't see anything about it that would cause a problem. I doubt it is the real cause here. It's just two PNG image grids and some XML, which is the best (fastest) way to package icons. Once loaded they're just images in memory which get drawn on the screen, the same as the internal icons.
I suspect the cause of the problem was something else which has gone away now, maybe after a reboot.