I second this, it is very important for people to know what kind of sign-up process is available and to be able to filter between them. Instead of a simple filter for "open signups" we should have a filter checklist which people can select to narrow the instances by registration type, "Open", "Requires Application", and "Closed".

It's important to note that "requires application" doesn't immediately mean it is open. I've seen a lot of instances use that as opposed to closing registrations since you can leave a message, or by using it as a form of invite-only sign-ups with registration codes generated by a bot, or by the admin. So it's not a great idea to phrase that as "open registrations" since there is no guarantee for being able to sign up to those instances.

The information is already in the data, just not filer-able in the UI, only Open or !Open:

The three registration modes are visible in the data:

"registration_mode": "Open"

This is always one of "Closed" | "RequireApplication" | "Open"

What about a similar three-state checkbox as the "Hide NSFW" behavior on the communities page.

1. All Instances
2. Open Registration Only
3. Closed Registration Only

Alternatively, thinking a dropdown could also be possible.

Maybe something like this multi-select one:

Also, there is this page but it's not linked anywhere

https://lemmyverse.net/join

The information is already in the data, just not filer-able in the UI, only Open or !Open:

The three registration modes are visible in the data:

"registration_mode": "Open"

This is always one of "Closed" | "RequireApplication" | "Open"

What about a similar three-state checkbox as the "Hide NSFW" behavior on the communities page.

1. All Instances

2. Open Registration Only

3. Closed Registration Only

Alternatively, thinking a dropdown could also be possible.

Maybe something like this multi-select one:

I think having a dropdown or list where you can select between open, application, or closed would be a good way of doing it, at the moment "open only" just shows all open and application ones, which isn't as useful. Would be good for people to be able to filter application ones as well.

I was thinking something like this, but the issue is you need to select two options (Open and By Application) to include all "Open/SemiOpen" instances.

Trying to think of a way to do it smarter, There's too many options for a checkbox, and space in the filter area is getting tight.