Calibre 6.0+ Switching from Dark Mode to Light after Editing Metadata and Reconnecting RDP

[Stephen Chu]

So I know this is a weird edge case scenario but here's my observed behavior and usage pattern.

I run Calibre on my windows file server. As a result I connect to it to add things/update metadata etc via RDP (Remote Desktop).

This file server is set to Light Mode but Calibre has been *explicitly* set to Dark Palette.

## Versions tested:
Calibre: 6.0 and 6.1

## Steps to Reproduce:
1. Open Calibre in an RDP session
2. Use the metadata edit dialogue to change something on a book
3. Disconnect the RDP session and then immediately reconnect.

## Observed Behavior:
Calibre switches from Dark Mode to Light Mode (*without* closing and reopening which is normally required to change modes) about 0.5 to 1 seconds after the RDP session reconnects.

Here is a screen recording demonstrating the behavior.

https://1drv.ms/v/s!Aj_p7RURjYgYjbIqGYzuttgy48O03w?e=fa6ijV

Initially I was provoking this via use of the FanFicFare plugin but you can ignore that part, it turns out this can be triggered in other ways. Fully closing restarting Calibre will return it to dark mode, merely closing it to the system tray and reopening will not.

I've waited for it to occur on its own without doing the RDP disconnect/reconnect and it **doesn't seem to be time based**. It appears to be **specifically triggered by the RDP session disconnecting and reconnecting**. This may have to do with the resolution and DPI being set/changed during the RDP? Not sure. I don't have a quick way at the moment to test if those will also provoke this behavior.

I've tried running Calibre in debug mode and it produces no events in the log after the change is made/when the disconnect and reconnect events happen.

[Kovid Goyal (kovid)]

Fixed in branch master. The fix will be in the next release. calibre is usually released every alternate Friday.

 status fixreleased