(EDIT: SOLVED. Not a bug at all. I accidentally set heal to auto-cast while wielding earth shield and the game remembers that)
Reproduce method:
1. Be a Catalyst (not sure if this is a required/necessary condition but I didn't reproduce this on my weaver/tempest)
2. Equip a heal skill & Summon Earth Shield skill..
3. Summon Earth Shield.
4. When I'm holding the earth shield, the heal skill keep getting auto-triggered.
I even went to Special Force Training Area to test this.
As long as I am holding the Earth shield, whenever I refresh skill CD (with special action), the heal gets re-triggered again.
This only happens on my Catalyst trait setup for some reason.
This doesn't happen for other conjure weapon skill.
This happens for all heal skills variant.
Swapping Summon Earth Skill around on my skill slot doesn't matter.