Awakened added lightning damage level 10 bug

The tooltip on level 10 awakened added lightning damage (possibly also the other added X damage) says that it adds +2 levels of supported lightning skill gems, but does not seem to add 2 levels.

I can confirm the same for Awakened Added Chaos Damage. I've compared it to Awakened Added Chaos Damage lvl 9 and even on my skill DPS thumbnail it seems like only the added damage from higher level support gem is being calculated, not the +1 level.

Yes can confirm, does not work. Only gives 1 skill level (lvl 11 awakened added lightning damage). Using Dialla robe, Venarius astrolabe and runegraft of gemcraft.

This bug seems to be related to how "+x levels from global modifiers" and "+x levels from item" are applied to the Awakened Added Lightning Damage support gem.

When "+x levels from item" are added to Awakened Added Lightning Damage to raise the level of the gem to 5 or above, then the "+1 to level of supported lightning skill gems" bonus does apply appropriately.

However, if "+ levels from global modifiers" raises the level to 5 or above, the text line "+1 to level of supported lightning skill gems" on the gem will show, but will not actually apply the bonus.

Here is a video showing the difference in how gem level modifiers from items versus global modifiers on Awakened Added Lightning Damage behaves in this case:

https://www.youtube.com/watch?v=PylTcbDTHOw