After the first run of the plugin replace the file /oxide/data/StackSizeController_vanilla-defaults.json

attached below

https://disk.yandex.ru/d/wXQzvqnDX20juw

You may notice in the description, it doesn't say literally anywhere to edit vanilla-defaults. Since apparently this has confused almost everyone using this plugin, I'll add a specific bold disclaimer. Read the description again, and modify the other data file. Vanilla-defaults is only there to restore vanilla stack sizes on unload, and editing it will do nothing useful.