Hourglass Support Gem shows for Artillery Ballista (Not Valid)

Steps to Reproduce
1. Equip Artillery Ballista skill
2. Right-click a Level 1 Support Gem
3. Select Artillery Ballista on the left
4. Notice Hourglass is a suggested Support Gem
5. Hover over it to see "Warning: This support can't be socketed into this skill."

Class: Level 33 Gemling Legionnaire (Mercenary)
Strength: 73
Dexterity: 46
Intelligence: 30

Also seeing this bug.
Hourglass is showing up as the middle level 1 recommended support gem for Artillery Ballista.
Hover over it to see "Warning: This support can't be socketed into this skill."