Usually when I resume a computer some apps do not show an indicator of multiple windows opened (not exatcly the same app always). When I relaunch the specified app then it gets fixed and I can see a white indicator at the bottom of the app's icon.
This report is insufficient for me to do anything about it, sorry - it lacks information about the apps involved, exact steps to reproduce, etc.
I noticed it several times but I do not know exactly how to reproduce the problem. What I do (usually 2x a day) is to suspend my laptop and then I resume it later. What I remember so far it has happened to me with Thunderbird and with Double Commander in the past as well. Today I opened a reply in Thunderbird and I could not see the indicator eventhough there were 2 windows opened in TB. Then I tried to open another window in Double Commander but there it was working fine, the indicator was present. TB and Double Commander was both running before suspending and resuming the laptop. When I closed TB and reopened it and the opened a reply I could see the indicator again. It seems to me so random so I do not know what to watch...
Maybe something to consider - I work on Dell Latitude 3510 FHD laptop and on 2 places where each place has a different monitor (1st is with 1920x1080 and 2nd with 1920x1200). And then between these places I work on the laptop itself with connected monitor.
Could you take some screenshots just so I can be clear which indicator we're talking about to make sure? The monitor stuff vaguely resembles bug 373075.
Created attachment 105963 [details] indicator I don't think I have met the same situation as described in #373075, I have had the problem with the indicator so far. My icons do not hide.
Unfortunately I have not been to replicate this issue since the time I have reported the issue. It's strange, at that time I could see the problem few times. Could it be that 5.10.1 or 5.10.2 fixed the issue? I will monitor it and if it happens again I will attach a screenshot.
There were no changes in the TM backend in 5.10.1 and 5.10.2 I believe. Thanks for keeping an eye out.
Created attachment 106611 [details] dc__no_indicator_1
Created attachment 106612 [details] dc__no_indicator_2
Created attachment 106613 [details] dc__no_indicator_3
Created attachment 106614 [details] dc__no_indicator_4
So it seems that this issue is not related to IconsOnly but right now it is happing for me with the regular Task manager. See the images attached on 14 July 2017 where I had no indicator for Double Commander process and its 3 windows.
Thanks for the updates; changing status.
Is there anything more I can help with? Enabling of logs, running special command etc.
Seems a bit like https://bugs.kde.org/show_bug.cgi?id=381656, where the volume indicator sometimes gets hidden with certain icon sizes. Can you try this: 1. When you do see a "multiple windows" indicator, try resizing your panel; can you make it disappear? 2. When you don't see a "multiple windows" indicator and one should be there, try resizing your panel; can you now see it? Please let me know if you can make either or both of those happen.
I don't use this plasmoid anymore while I have seen it too complicated for daily usage but I tried to replicate it with the steps you described and I was unable to replicate the issue... What I have seen is I added a new panel with 1 plasmoid (icons-only TM) while Chrome (no audio) and Spotify was running and playing and there was no audio indicator on Spotify's icon. When I started to play audio in Chrome, audio indicators appeared on both Chrome and Spotify icons.
And you are or are not able to reproduce that issue now in Plasma 5.11.x?
I am now on Plasma 5.11.4 and I am not able to reproduce the issue.
Excellent news, and thanks for testing again!