I've used 1P to Fill & Submit for years but recently started to notice it's input being rejected by many sites. (Safari Version 6.0.5 - OSX 10.7.5)
Here are some examples - but I've seen this type of behavior on an increasing number of other sites as well.
- Chase - Auto Submit doesn't happen - one has to mouse over and click login/submit
- Discover - Fills OK but it doesn't "see" the password - even though it's filled in - it reports - "Please enter a password." I have to type or paste it in again manually.
- Capital One - Doesn't fill in the User Name - even though the Username field in the program has the valid credentials.