I had it for about two years.
Tried many things and in the end it was a multi pronged approach that fixed it.
Every morning before I got out of bed:
Make a circle with my toes, rotating from the ankle. Circle gets bigger and bigger and in doing so you are stretching the PF.
Also, have 3-4 pairs of running shoes. Never run two consecutive days in the same shoes.
And on a daily basis:
Stage 1: Tennis ball in work.
Have a tennis ball in work - gently roll/massage the foot pretty much whenever I think about it.
Stage 2: Tennis Ball
Massage deeper, roll harder. Aim fir dull pain - if you get sharp pain then you’ve overdone it.
Stage 3: Golf ball.
Interchange golf ball with tennis ball. Gentle with the golf ball. Hard with the tennis ball.
Stage 4: Golf ball only
When PF is gone. Keep the gold ball as part of your routine. Once twice a day. Not too hard, not to gentle. Aiming for dull pain.
This cleared it completely for me in a few months.
Was it the runners?
Was it the massage?
Was it the morning foot warm up?