Slowly Stamp Collection Compare Tool v.0.3.6
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Also display missing stamp names.

If you skip entering First Collection, this toool uses a Slowly WIKI Reference one.

Or select one of the Alternative Reference Collections :

Friend 1's Collection. Friend 2's Collection.
Friend 3's Collection. Friend 4's Collection.

Note : These alternative reference collections should be modified - edit the Compare_script.js file.

In the first few lines at the top you will find the place to enter your own Friends Collections links.

See the Blog post with a guide on how to use this tool here. Or visit the Reddit Topic here.