Guild Wars 2

https://www.reddit.com/r/Guildwars2/comments/6u622i/patch_notes_16_august_2017/dlq7r9l/

if you have the signet trait, put a signet in the right-most utility slot (9). Then move it to the middle slot (8). It gains a stack of the buff if you do this. Then move it to the left-most slot (7), it gains another stack for a total of 3 stacks. You can do this with another signet and put it in the middle slot to get 2 stacks. Tons of free power or condition damage.
It might not show up in your buff bar, but look at your hero pannel stats

Can confirm it is indeed bugged.