The symptom of the problem you relate to here may have something to do
with using Mission Control, or perhaps alleviated by using M.C. settings.
Mac Basics: Dashboard gives you quick access to frequently used info - Apple Support
Use Mission Control on your Mac - Apple Support
While I seldom rely on DashBoard in newer OS X, I did find a few older widgets can
and do work OK in Mavericks 10.9.5 Dashboard that had worked well in OS X 10.5.8
in an older computer I'm still using most of the time. Because I saved the widget .zip
files I have some that are not widely available anymore; or not in Apple widget page.
One I sometimes use was Dashquit_3.0 since it can cause the OS X to refresh or
remove issues saved in memory of the Dashboard application; so the desktop runs
faster and other apps work better if I've quit Dashboard using this in Mavericks.
Even after re-starting Dashboard the effect of forcing it to quit, lasts. So I use it.
Another is iStat Pro v 4.92 (old version) as it still works in OS X 10.9.5; I'd saved a
zip file of that one too, but then looked through and found a link to old mirror D/L
and that has a clean download of the vintage one I had saved two/three years ago.
Perhaps you may have to restart your computer in Safe mode (shift key held down
through startup) and then see about repairing permissions in Disk Utility, then restart.
This may help. Another idea if you have to user accounts, is log out of the main acct
and log into the second one. This avoids restarting, if that matters. My macs can do
just fine if let sleep; as they have UPS battery backup with power filtering abilities.
Not sure why your Dashboard (and safari) have exhibited the symptom you cite... 😐