1. Open your photo album where you've uploaded some photos.
2. Click the little dark grey "link" icon below the thumbnail
3. Return to the forum post and paste (CTRL+V or CMD+V) or right mouse click > paste.

Will take a little work to make it work on mobile due to the formatting but it should save some time for some folks.
It works better if you use 2 browser tabs, one with your post editor and one with your photo gallery opened.
Screencast demo (added 9-25-2018):




