I occasionally use Nextdoor to list items for sale, or to see what's going on in my neighborhood and surrounding area. I have to say, I like Nextdoor since it allows me to connect with my neighbors in a relatively locked-down place, even though I'm sure most of them are in local Facebook groups already.

However, I don't like seeing sponsored content. Period.

Here's how I managed to hide sponsored posts on Nextdoor.

Using Pi-hole

If you have a Pi-hole set up on your network, go ahead and add the following to your Blacklist:

flask.nextdoor.com

I added it as an "exact" filter and it seems to work fine.

Using uBlock Origin

You can create a custom filter in uBlock Origin that blocks the following domain:

||flask.nextdoor.com/events/*$xmlhttprequest,first-party

Add the above to the end of your filters on "My filters" in uBlock settings.

Disclaimer

I expect this to break in the future as Nextdoor catches on (or finds this post!) and as ad-serving becomes more sophisticated.