Created attachment 104040 [details]
Simple case

For example, in this simple case:

Created attachment 104041 [details]
After the start button was pressed

If the "Synchronize" button is pressed and then the "Start" button is pressed, then Krusader does not respond. 

if Krusader is closed and it's executed:
    ps aux | grep -i [k]rusader
then it is seen something like this even when Krusader was closed:
    user     13698  0.6  5.1 718532 82304 ?        Sl   08:13   0:06 /usr/bin/krusader
    user     13733  0.0  1.0 290172 15996 ?        S    08:25   0:00 kio_krarc.so [kdeinit5] krarc local:/run/user/1000/klauncherTJ1377.1.slave-socket local:/run/user/1000/krusadern13698.4.slave-socket
and then a command like
    killall krusader
must be executed to regretfully do that to our dear Krusader :-)

Thanks for Krusader!

Syncing archive content seems not to be supported at all right now.
Solutions:
1. Check if user wants to do it and abort with error message
2. Make it working

(2) is more complicated, of course. But maybe it will be be a fortunate side effect after I simplify the code base...