Companions not gaining buffs when entering combat from a mount.

[Laiov]

Normally when you summon your companion, out of combat, the companion automatically gains all of the class buffs that you yourself have. Hunter's Boon, Unnatural Might, Mark of Power etc. When your companion is summoned in combat, however, as when you ride a mount directly into a pack of aggro and begin fighting, it does not appear that the companion gains these class buffs until combat is over.

 

This is problematic in high aggro areas like Makeb or Oricon, where mount-to-combat scenarios are common, or in any questing scenario wherein there's competition for a clickable quest objective (something that you need to pick up before you kill the surrounding mobs).

[Cernow]

I'm getting the same. I can confirm it's not just a display bug. If you watch the companions stats, they are lowered on dismounting and only rise back to fully buffed after the combat has ended, when the buff icons reappear.

[Excise]

Also seen this issue crop up.

[JLazarillo]

This isn't a new bug. I generally figured it was because the companion has to "activate" the various buffs, and those are second fiddle to activating a stance...so once combat starts, they don't really get a chance. Who knows, though.

 

As a side note, activating stealth while on a speeder will also summon a buff-less companion.