Certain emojis don't stick on some instances/platforms

A pleroma user noticed that certain religious emoji reacts like the star of david and cross are not sticking on some instances (kf, spc). They will appear in the react initially, but upon refresh they are gone.

However on my Pleroma 2.2.2 on apache + fedora linux, they do stick. Confirmed working on after a refresh.

Not sure if this would be a back end or front end issue, but admins of KF and SPC said they are not blocking these emojis.