When trying to add (I replaced www with wxw and . with (dot) to be allowed to post)
wxw.l9f(dot)org/index.php?f=eq2stuff.co.cc-cursor-calibrate.png&fo=5dc09f57a0da73231eda8f dca7aca57ef8a84cdd
as an image, it ends up as
[imgs=wxw.l9f(dot)org/index.php?f=eq2stuff.co.cc-cursor-calibrate.png&fo=5dc09f57a0da7323 1eda8fdca7aca57ef8a84cdd]test[/imgs]

Note the space between 7323 and 1eda.

mini bb places that spaces itself.. probably because the url is so long it ends up on a new line, this causes the img url to break and the [img] tag to be shown as plain text.

It's because the URL to the image should end with a valid extension. Remove the "&fo=5dc09f57a0da73231eda8f dca7aca57ef8a84cdd" and it will work.

Such URLs are not allowed for security reasons.

Thanks for the reply, but I added rewriting to the site that hosts the image, and the URL still breaks

[imgs=wxw.l9f(dot)org/dl/5dc09f57a0da73231eda8fdca7aca57ef8a84cdd/eq2stuff.co.cc-cursor-c alibrate.png]test[/imgs]

Notice the space between "c" and "alibrate". This should be a valid URL for miniBB to handle, but I guess it has trouble handling long urls.