My favorite, most precious piece of software, 7Stacks, works like poo on Windows 10! In Windows 8.1, all the shortcuts and icons would load instantly when I'd press on the stack button in my taskbar. In Windows 10, first time clicking any stack results in very slow loading of icons/shortcuts. Consecutive pressing does result in icons/shortcuts loading quickly. Its like Windows 10 searches for programs connected to stack's icons/shortcuts... I turned off Search services, but that did not help the problem. Does anyone know how to get 7Stacks to load quicker first time a stack is clicked on?
Wait for a 7Stacks update. You can't expect especially software with deep system integration to work on new OS out-of-the-box. This is not any Windows 10 issue.
There are no good alternatives. What would I set to Windows 7 mode? Each stack is just a taskbar shortcut - I don't think Windows 7 compatibility mode can be selected.
I re-formatted SSD and re-installed Windows 10 without installing any Windows 8.1 tweaks/fixes/NET Framework, etc. This time 7Stacks works fine, but I think the original cause of the issue was me disabling Security Center service, since I've done that in Windows 8.1 and it never affected anything and even let Windows Firewall work without that service.