This doesn’t happen to me with latest master, nor with 2.81… but it does refresh when hovering on the navigation buttons and generally every time there’s a redraw in the 3d view (changing the cursor location also triggers it).
Found this in d.b.o https://developer.blender.org/T65821#715202 Clément seems to aware of this kind of problems.
have you tried with soft shadow enabled?
I noticed that the refresh concerns only some features, like the soft shadow, global illumination and other things like that … especially the phase that must “do the final sampling”
Yes I did, I think the refresh happens anyway, but it’s way easier to notice with those settings since they depend a lot on the samples count.
Maybe it’s an OS dependent thing (I’m using linux) in that case it would be another layer of complexity, and might be worth it to submit it as a bug.
in fact it is on windows, but it is strange that there are this kind of differences
I’m not sure it can be defined as a bug, so I preferred to report it as a papercut
I tried it on windows10. also not happening here with 2.82 ( softshadows are turned on and i can force it to trigger redraws, but not how you did it)
Edit: Just updated to latest build. Still not happening, just if the cursor is the resize symbol (hovering over area between the tabicons and the tabcontent and clicking)
The following shortcut toggles between Edit Mode and the Last used mode for Mesh objects but behaves differently with grease pencil objects.
I want to toggle between Draw mode and Edit mode but what it does while I am on Draw mode is: on first press it goes to Edit mode but pressing again takes me to Object mode instead of going back to Draw mode. Afterwards it simply toggles between Object mode and Edit mode.
This really gets in the way of smooth grease pencil workflow. Please fix this.
At this point I don’t know what happens, maybe something limited to my hardware? 
Hmm. Not really sure if this can be a hardware thing. The redraw is somehow triggered by the UI. Just tried it once more and I found a way to trigger it. Don’t know if that has been the your case. But if the rendering in the viewport hasn’t finished, then a click on another tab will restart the 3dviewport render. So what I did was to set the number of samples to unlimited ( =0) and started to switch tabs. Was that also your setup?
Could you try the last build?
Edit: I can confirm that happens in my pc also.
Ok, can confirm this as well doing so.
I forgot … you have to set the light radius greater than zero otherwise the softshadow will not fliker and you don’t notice the refresh.
the samples are the default ones 16
I tried it with an area light 4 by 4 meters in size, redraws were clearly visible.But also with a point light and a bigger radius it doesn’t behave like what you demoed. If you already tried the latest version, try it again with updated GPU drivers. As you said it’s no big issue, but if it still doesn’t work with updated drivers I’d say write a bug report, might be a useful info for the devteam.
Edit: Thanks for the info @a.monti 
Also adding to that redraw bug I’d really like soft shadows redrawing to be paused completely while move, rotate and scale tools are active. This will provide much smoother workflow.
It’s nice to be able to preview soft shadows in a viewport, you actually want them on, but so much flickering will kill you and you are basically forced to turn them off.
After introducing PCF shadows and Soft Shadows on by default it’s redraw logic needs to be reworked badly otherwise there is no point in Soft Shadows on in a viewport.
when using Unit system in a scene, one cannot copy Number field with units into the unitles field.
For example when set to meters. I cannot copy value from X location into the Scale field(which is unitless)
That sounds like more than a tiny thing. This means that “ctrl-c” is copying the text that is displayed in the input, instead of the actual value. This would also have other implications since we sometimes show inputs with less precision than they are stored.
You should submit this as a bug.
Edit: It is copying the full precision of the input to the clipboard, not just what is displayed. So the only error is that it is including the unit.
There is a useless header at the bottom of file browser window, and also it features a mispelled (and ambiguous) “Move Files” entry
Also using that Recent menu returns error
Just wondering… wasn’t collections also in the list of possible things to rename in the new batch rename tool? Would be cool to have it. Manually renaming a bunch of
collections is a pain in the butt.
I have verified that in version 2.81 and 2.82 of today, in Windows, selected a bone of an Armature in Edit Mode and pressing Ctrl + TAB shows a Pie Menu with (Object, Edit and Pose Modes), but once you change mode to Object or Pose, does not appear again.
I find this very confusing, I think that Ctrl + TAB should always show the same Pie Menu.
I know that Shift + TAB and Shift + Ctrl + TAB conflict with the Snaps, but if there is no better solution, perhaps it is even better to eliminate the Menu Pie.
So tiresome to have to remove instances and then re-link everything all the bloody time.
No other app I know of does this. Max just applies modifiers to all instances seamlessly, and for example Rhino (a different kind of 3D app, but still) just says that this broke the current instance and you need to re-link.
