Trouble after upgrade to Linux Mint 20.3 Una (Mate)

[Marek-Moehling]

Since upgrading to Linux Mint 20.3 Una (Mate) from 19.3 KDocker takes ca. 20 seconds till the mouse cursor converts to a kDocker pointer. Same applies to e.g.:

kdocker -d 5 -qi /usr/share/icons/Mint-Y/apps/48/thunderbird.png thunderbird;

It takes ca. 20 sec. till the icon appears in the dock.

Kernel: 5.4.0-96-generic x86_64 bits: 64 compiler: gcc v: 9.3.0 Desktop: MATE 1.26.0 Distro: Linux Mint 20.3 Una base: Ubuntu 20.04 focal