I have my taskbar set to show a single icon for each program, and rely on mouse-over to let me quickly bring a specific application's window to the foreground. Since 9.0b3 the mouse-over behavior has begun to randomly stop. When this occurs, clicking the taskbar icons also fails to elicit a response; that ought to bring single-window apps to the foreground or show the mini-previews, just like mouse-over.

It's happened twice so far in as many days, and each time it can be resolved by right-clicking the taskbar and clicking "Settings". Once the DF settings UI opens, all is well.

This may or may not be related: each time I right-click the taskbar and choose "Settings" or "About", DF opens behind the foreground window. What's interesting is it only opens behind the foremost window; it's not positioned at the bottom of the Z-order, it's simply one below the topmost.

I have set logging to L1; should I set it to L2 or L3? Or is L1 sufficient to capture any useful data?

Here is the log. It's happened multiple times, but most recently twice within the last 20 minutes, so check the most recent log events. I had MPC-HD open and the taskbar stopped going into the background on fullscreen; I also could not un-minimize Windows Explorer windows, though all other programs un-minimized just fine.

I exited DF 9b3 and restarted it, and the taskbar went into the background properly; I could also un-minimize Explorer windows again. I then took MPC out of fullscreen and back to fullscreen, and the improper DF behavior returned, including the problem with Explorer windows.

I restarted DF again, and the issue went away again. Hopefully the log file is useful.

Edit: to clarify, the issue with Explorer windows is the same issue as my initial post, where mouse-over or clicking the icon fails to show the minimized window previews, etc. I'm mentioning the taskbar-fullscreen bug because I've now discovered they only occur in concert, so they are likely related.

Now that's interesting -- I hadn't even noticed Screencast-o-Matic was running in the background. The program itself is closed, and I wasn't aware it had any persistent processes (but I do see one now that I checked). I will definitely try killing it next time it happens. I'm dubious, though.. the problem is only affecting Windows Explorer windows, other apps restore fine. But you never know.

Ok, so it looks like the issue is not Screencast-o-Matic; it JUST occurred again, and killing that process did not resolve the issue.

Here's what occurred:

• I restored a Win Explorer window, double clicked on a video file, and minimized the window. Thus, minimizing/restoring Windows Explorer windows worked fine at that time.
• MPC-HC (default mp4 player) was now open; I started playback and put the video into fullscreen on my second display (the one with the DF taskbar)
• Immediately noticed that the DF taskbar was remaining on top of the video.
• Tried exiting and returning to fullscreen -- no dice.
• Exited fullscreen again and tried to restore the Windows Explorer window I'd minimized in step 1. Windows Explorer window would not restore, and mouse-over didn't show the previews of all open WE windows, as would be normal behavior.
• I used Task Manager to kill the screencast-o-matic.exe process.
• Tried restoring WE windows and playing video fullscreen -- no dice.
• Right-clicked DF taskbar and chose "Exit". Then re-launched DF from Start Menu.
• Windows Explorer windows now show previews on mouse-over in taskbar and restore when clicked. Taskbar also goes to background when MPC-HC is fullscreen.

I'm attaching the complete log file; this whole situation transpired less than 5 minutes before I exported the log, so you shouldn't have to look back far.

Thanks for your help!

Ok, this is very interesting. Once DF is bugging out, ANY app which goes fullscreen is impacted: the taskbar remains on top. However, the trigger is simply launching MPC-HC (I'm running 1.7.13-x64 but it occurs with the previous release, too).

Steps:

• Open something fullscreen (been using YouTube in Chrome-stable), works fine.
• Launch MPC-HC (don't even load a video) (or load a video, no difference. Just not required)
• Open something fullscreen -- DF is now stuck on top.
• Exit MPC-HC and then restart DF
• Fullscreen back to working fine.

You can repeat this ad nauseum, it occurs 100% for me. Attaching log, just did it 3 or 4 times in a row. What's very interesting is that if I leave MPC-HC running while relaunching DF then the issue is gone temporarily. MPC-HC will go to fullscreen fine once or twice after relaunching DF, but after a random period the DF taskbar gets stuck on top again (but only if you exit and reenter fullscreen, it doesn't suddenly pop to top during uninterrupted fullscreen).

When the taskbar suddenly comes back to top it happens like this:

• Exit fullscreen
• Reenter fullscreen
• DF taskbar is on top, then pops under after a moment (this is ordinary behavior)
• DF taskbar flickers as if trying to pop under, then gets stuck on top permanently (this is error behavior)

I'm also curious why MPC-HC is hanging for you; that's fascinating.

As I obviously have Screencast-o-matic, let me know if you think a screencast would be useful. I can demonstrate both scenarios, opening DF first, and opening DF second.

One other thing to add: when this occurs, if I press the Windows key or click the Start button on the main monitor (the one with the Windows taskbar) the Start menu always opens on the DF taskbar monitor. It's as if DF is stealing the Start menu, even when it shouldn't open on that display. This resolves along with everything else if I relaunch DF.

Just as an FYI: I am seeing the same behavior... I've attached the log FYI...

I can copy the OP's first post, but that seems kinda stupid...

It 'just happens' after a while... Cannot pinpoint it, or tie it to a specific application...
(Right now, for instance, it isn't working again! I have no clue why!)

PS: I'm on the latest stable: 8.1.2

As requested...

IDK, I'll have to test that... I will turn it off (reluctantly) and let you know in a while...
(Is this a known bug or something?)

I disabled auto hide when window preview was working. Window preview is NOT working anymore right now, and neither is opacity/transparency... (Never noticed that before due to Auto-hide, so IDK whether or not that was an issue before!)

Attached my latest log, FYI...

I never use autohide; it's always disabled on my machine. Conversely, if you think enabling auto-hide might rectify the bug I can try that, though.

Ok, pls keep us posted! It's pretty irritating!