Dandy description of the symptoms. The common cause of this is rust build-up inside the crimped-on mounting bracket in the middle of the front hydraulic hose. The red arrow is pointing to the place you need to spread open a little. Use a large flat-blade screwdriver or a large pair of pliers to open the bracket a little where it's crimped around the hose.
Your best observation was the caliper releases when the bleeder screw is opened. What you will also find is that brake does not release when the steel lines are loosened at the master cylinder.
If you find the outer cover of the hose is cracked, the hose must be replaced. To make that job easier, use a stick between the front seat and brake pedal to hold the pedal down an inch or two. That will run the lip seals in the master cylinder down far enough to block fluid flow while the hose is off. That will prevent the master cylinder from running empty while the hose is disconnected.
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Tuesday, December 14th, 2021 AT 9:02 AM