What filter are you using exactly? Have you tried Fill with resynthesized pattern?
Images need to meet certain criteria in order for the plugin to work.
Resynthesize plugin usually comes as a bundle with some Python scripts. If you have this set, all plugins there are functional.
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Other possible reason for the plugin crashing or not executing could be that your system is not powerful enough.
Try to assign more PC resources to GIMP in Preferences. Increase Tile cache size.
Resynthesizing process is slow and very resource consuming.