Imgur now blocks several VPNs and have issues loading embedded previews in several fediverse platforms. So instead of using imgur, you could use one of the following alternatives for uploading your images.
https://postimages.org/
https://imgbox.com/
https://imgbb.com/
https://www.imagebam.com/
The ‘catch’ is that running a service like this gets expensive fast and it’s the same with all the free image hosting sites.
Catbox is run entirely by donations with anything left covered by the owner out of their own pocket. If the donations dry up, it will eventually have to shut down. Again, this isn’t unique to Catbox, all the free sites could easily suffer the same fate.