Imgur.com is a great choice with it's handy (optional) Edit feature.
And it can upload images directly from the web to your albums.
; Browse or Drag/Drop from your computer.
Or get the image from a web page. Use right mouse click on the image for the image URL.
Check the Edit Box if you plan to edit an image.
(optional step) Advanced options shown. *
You should have checked the Edit Box in 1st step if you plan to edit an image.
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: Use BBC Code and copy/paste into the forum post.