__Turn off animated mouseover effects:__

In KDE, go to the main Application Launcher button --> Control Center --> Desktop --> Panels  (or open "kcontrol" from an xterm)

Click the Appearance tab

Uncheck "Enable icon mouseover effects"

__Turn off GUI effects:__

In KDE, go to the main Application Launcher button --> Control Center --> Appearance & Themes --> Style

Click the Effects tab

Uncheck "Enable GUI effects"

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