Guild Wars 2

How does Boon stack with different timers are calculated ?

For example:
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Warrior casting “For Great Justice” which gives Mightx3 (30sec) + Weapon with Sigil of Strengh (30% Crit for Might 10sec).

What I would like to understand is, does this boon co-exist in a different timer or which one of it overwrites which ?

Also, I’m hearing Sigil of Strength is bugged, what is the bug anyway?

There is no 6-tier bonus.

Stacks have individual timers and expire in queue/order of application. So, if you already have 25 stacks for 30 seconds (no skill would do this, but just for outlining mechanics…) and someone afterwards gives you 3 stacks for 5 seconds. You will now only have twenty-two 30-second stacks and three 5-second stacks (still 25 total), and after 5 seconds you would fall back down to 22 stacks for the remaining 25 seconds.

The bug is on the rune of strength not sigil of strength.