I did not understand a word you just said
Viewing post in Actual working tag exclusion
You tried to open a Javascript-File from my project and got an error message. Did I understand that correctly?
If so, it might be better if you reply/comment on the project page, as troubleshooting will go offtopic here.
I have several files on that project that are Javascript. And none of them is supposed to be opened. The zips are to be installed. And the two .js files are supposed to be imported into a browser extension called Tampermonkey.
That's strange.
If this is the genrefilter, the games must have the genre set as their main genre. It will not block games that have that genre set as a regular tag.
If this is the button for the single tag exclusion, you need to be logged into your Itch account while browsing for the feature to work (has nothing to do with my script). And you need to enter the tag as seen in the url without the prefix. So if the tag is shown as genre-visual-novel in the url, you enter visual-novel. If it is tag-3d-platformer, you enter 3d-platformer.
Both those tag blocking options work on my system, as I just tested. I am on Chrome.
You need to enter gay in the box.
To use the exclude feature, you transform a tagname into the url modifier as shown here
https://itch.io/games/genre-visual-novel
https://itch.io/games?exclude=tg.visual-novel
What the tool does is, to give you a box to write in "visual-novel", so you do not need to manually add "?exclude=tg.visual-novel".
And it also makes this url change persist. For a recurring search, you can also just simply use a bookmark, no need for a tool.