It's a common user error: Instead of entering the drop rate in the "1 in X format" that Rarity uses to represent drop rates, people will (try to) enter something like "0.4%" as taken from wowhead.

Now, this could mean that the explanation (tooltip info) isn't prominent enough, it is too long, or it's just too confusing. In this case, it might be worth just accepting the format isn't well designed from a UX perspective because non-technical people don't think of probabilities that way.

So I propose the following changes:

• Ideally: If user enters a regular number (no "%" or "." or ","), use the old format to avoid surprises (problematic! See below...)
• Otherwise, parse it as a floating-point percentage and interpret according to the internal format
• Different locales use different comma separators, so this must be accounted for

HOWEVER: Entering "4" could mean "4%" or "1 in 4". Since the differentiation is unclear in these cases, maybe the actual drop rate that will be used should be displayed prominently, right next to the edit box, in BOTH formats, so it's clear when the number entered is wrong/not what was intended. Then we can just use the "new" (human-friendly) format?

Does that solve the problem? Not sure. Is it too complicated? Maybe. Will people actually find it useful? Would have to ask them...

Feedback on this would be very welcome. I don't know if it's actually useful/how people want to work with the drop rates.