Hello Andreas,
I am looking at 5th Edition OGL by Roll20.html and trying to figure out how to make some changes to how it works.
My favorite "looking" sheet is definitely the Astonishing Sorcerer's and Swordsman of Hyperborea as far as layout and function, however, given that I plan to mostly use a slightly modified set of D&D rules, I was looking at the 5th Edition OGL by Roll20 since it is very compatible with D&D.
I have been going over a few tweaks for how I would plan to DM the games:
In my games, I plan to add a "Skill Level" for different weapons. under the "Attacks and Spellcasting" list. (It would be similar to something like the player's generic level for say fighter or paladin, but specific to the weapon they are using. (You can think of it as a Proficiency Level? but the actual Proficiency check box would be ignored)
Fortunately, there already appears to be an empty field ( attr_atkmod ) for what looks like any numeric value I want in that location, so I just need to reformat the rows to display the word "Level" between the NAME and ATK columns. and display the attr_atkmod in the Level Column.
Here's what I am planning:

ANYWAY: I have isolated this: attr_atkmod from the .html and it appears to be an empty field as shown in the above pic. on the char sheet.
However, that exact name "attr_atkmod" is only in the entire doc 1 time. So, my assumption is the attr_ prefix is somehow stripped off.
BUT.. I don't understand where all the ATK modifier stuff gets added in and shown as 1 number in the column under ATK. (when not in edit ode).

So I am trying to hunt down where that might be in the html... so I can try to change the output slightly.