How can you filter out certain content on lemmy?

See rule 5

5) This is not a support community. It is not a place for ‘how do I?’, type questions. If you have any questions regarding the site itself or would like to report a community, please direct them to Lemmy.world Support or email [email protected]. For other questions check our partnered communities list, or use the search function.

I just ban the posters. It gets better quite quickly, as it's a loud minority of people spamming the stuff.

In Boost - Settings - Filters and Blocks - Muted Words

Only works on subject lines though.

Support question. Locking.

Mlem has a filter list

You can't do that on the web client. You have to find another app.

IIRC, it's slated to be added, but hasn't been yet.

Mlem also allows blocking of keywords