It's been two weeks now where, during an involved combat, the entire encounter crashes while clicking between stat blocks.  I lose my initiative numbers and current monster HPs.  This has happened numerous times even upon a reload of the encounter.  The only noticeable difference it seems is that many of my recent stat blocks have been homebrews and it's been more common since rolling on stat blocks have been introduced.  I use Roll20 and the Beyond20 extension to play, so perhaps there's an issue there as well.  Anyone else having this issue?  If so, any resolution or ideas to avoid it? 

I tried it, and that does seem to be the case. I suppose this is something that we would need to take up with Beyond20 then?

I fixed this issue. In beyond20 settings, there is an option that says 

• Replace Dices formulas in D&D Beyond (Stat blocks)

  In D&D Beyond, if a dice formula is found in the stat block of a creature, monster, vehicle,

  enabling this will add a dice icon next to the formula to allow you to roll it.
  
  

  Disable this and encounter builder should work again
  Edit: It seems you need to toggle it each time you load a new encounter, but still works

THANK YOU!

I've been struggling with this for months! Had to resort to other initiative trackers, not realizing it was an issue with the Beyond20 extension. You're a life saver!