Right now, to open a sheet in its own window, you have to enter your game, select the character, open the sheet, and select the “open in a new window” option.
It would be nice to be able to open a sheet from within the game’s Portal (in the same way that Dice Roller and Combat/Audio "Add-On"s may be opened). In fact, there’s already a “placeholder” of sorts for Player Characters in the UI for the portal:
I was told that this hasn’t been fleshed out because they’re prioritizing the community votes in this forum. So… would you be interested in something like this?
Players with slow Internet connections or slow PCs (or both) could open their sheets a bit faster, or open them in between sessions just to check how much XP they need for the next level.