sorry for the late reply! i accidentally left a french .txt file inside the locales folder that had the russian word "копия" in its name, which broke the extraction on linux because of the non-utf8 characters.
i just re-uploaded the fixed file, so please try downloading it again. or, if you prefer, you can just rename `BrushManagerPro_v0.9.7.1.aseprite-extension` to `.zip`, delete that txt file from the locales folder, and rename it back to `.aseprite-extension`.
sorry again for the trouble xd