Maybe I’m overthinking this. I want something with a drag and drop interface that then gives me a link to paste into discord or a forum to show the image directly, as Imgur does.
I could just use a bare web server but I’d have to scp the images over every time.
If it’s just for you, then you don’t need to tackle the hardest problem of content moderation.
The second hardest problem is bandwidth. If you post something to a forum that suddenly gets a lot of traffic, without some kind of CDN intermediary, you’ll get a hug of death and/or a huge bill for all the bandwidth.
The third hardest problem is uptime. My assumption is that you want the content to remain valid forever. No one likes seeing dead links in old forum threads. So as you use it over time, anything you’ve posted over the years could get a sudden unexpected viral hug, or you have to let it die (which may not necessarily stop the hug, since everyone would still be trying to ask your server for the content).
Just making sure you appreciate how difficult solving this problem inevitably becomes. Note that discord and Lemmy Posts let you upload images, so you shouldn’t need such a service in those cases. But for random forums, it quickly becomes hard.