Never experienced this on any other bike in the past.
Started about two weeks ago when I was applying front brake pressure and the lever stopped moving but I still needed more braking power so I squeezed harder and got more brake but it was very jerky. It's been getting worse to the point that if it was raining I think the front end would be skidding as the brake lever jumped when more pressure was applied.
Took the pivot pin out and cleaned the pin and bushing and put some oil on it and reassembled it, squeezed the lever and still had the same symptoms. Then looked at the point where the aluminum of the brake lever contacts the steel of the brake plunger in the master cylinder and it seemed to be corroded. Cleaned off the corrosion and put a dab of grease on the contact surface, put it back together and it is smooth as new.
No leaks from the master cylinder so all is good.
If your front brake is grabbing a little dab will do ya.
