If you used Gimp’s filters, you probably wished it had more of them. And it does, you just need to install them separately. G’MIC is a popular and vast collection of great effects.
Installation
Head to gmic.eu/download and choose version for your system from “G’MIC-Qt plug-in” section. On Linux, extract plugin file from archive and put it in plug-ins within your Gimp directory. For example: /home/vllur/.config/GIMP/2.10/plug-ins.
Usage
Now you can launch a new window by navigating to Filters and G'MIC-Qt....
Some filters might need more inputs, for example two layers. You need to select them in Gimp before launching G’MIC window.