Who is this for? People who write lots of regular expressions won't need it because they know what they're doing and people who don't write lots of regular expressions probably won't find it anyway.
It just seems like a weird type of user who actually wants this.
My favorite password is the string "a", but I never get to use it anywhere due to these ridiculous restrictions 😔 Can you tell me which online services you administer so I can sign up for them and enjoy unfettered use of my favorite password?
You mean like this? 
Lemmy already has image hosting; your instance may or may not support it.
Voyager doesn't show the inline image above, but it's there. Check out how this thread looks in a browser on a Lemmy instance and you'll see it. You can even reply and attach your own image, just like I did.
I suspect there is a better solution for thumbnails, but not sure if it's you or Lemmy devs who would have to fix it.
This is how thumbnails look on my device, basically anything with text is completely unreadable:
This image, for example, is 109KB https://lemmy.world/pictrs/image/7fd7eeaa-f466-4697-8ea9-2f16e4372adc.jpeg
This is what Lemmy generates for it at thumbnail=128: https://lemmy.world/pictrs/image/7fd7eeaa-f466-4697-8ea9-2f16e4372adc.jpeg?format=jpg&thumbnail=128
And this is what my local imagemagick makes when asked to resize the original to 128w at 50% quality: https://ibb.co/ZgT35p4
Lemmy image is 4906 bytes and unreadable and the Imagemagick is 1398 bytes and you can make out the text.
And that's before getting into cropping etc. Basically, there's room for improvement, somewhere.
Edit: seems like pict-rs (the library Lemmy uses for image hosting) uses imagemagick to compress images, so it's probably just to do with the selection of filters/options they've chosen.
Sorry, I see that now! All the Sync comments in your screenshot must have confused me.
I think this is not really inline with the philosophy of the main Lemmy devs. For this to happen, I think someone else would have to do the work of creating the random selection service. If it was popular enough, maybe they'd put a link on join-lemmy.org
Easy, just create the equivalent of multireddits.
I've been oscillating back and forth between wefwef and Connect and think I'm likely to stick with Connect.
I love all the customization options, they really let me change the UI to the way I was used to with RiF.
One thing I'd ask for is an option for text posts to have a dummy thumbnail so that all submission entries have the title, submitter, community, comment/vote counts in the same place. At the moment posts in the list without a thumbnail look a bit disjointed.
But this community is for Connect for Lemmy? Did you post a screenshot of a different app?
Can your instance not do that as is? Just spin up a bunch of fake users and make them all vote on something?
But you can do that already in many languages using extended Regex syntax.This doesn't add anything except more verbosity and another syntax to learn.