Action Details
Requirements and how-to articles for Twitter's action:

Requirements
You need this to get it done:

Photos or animated GIFs
File format: .gif/.jpg/.jpeg/.png
File size: Static photos can be up to 5MB; animated GIFs can be up to 5MB on mobile, and up to 15MB on web.
One tweet can contain up to 4 static images, or 1 animated GIF.
Looping GIFs are supported. If your animated GIF doesn’t loop and plays a single time, it will display as a static image.
Tweet Text (optional)
Add text to accompany the shared photo or GIF loop (maximum of 280 characters.)
Requirements missing or found errors? Report

How-To Articles
A list of useful links for you:

0
Twitter Help Center - How to post photos or GIFs on Twitter
Information about photos and GIFs on Twitter including advanced options such as tagging, protection and who can see what etc.
Official
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