Anyone have/had a "Baker's Knee Cyst"?

have not had that but have had swelling both under the patella and in the back of the knee.

Rest,, Compression (bandage or brace) and Elevation as much as possible would be my suggestion along with medications etc to reduce the inflammation.

Keep leg up as much as possible. Do not immobilize however, you want to maintain your range of motion.

Gosh. Talk to your doctor.

I had a ganglion cyst on my left ACL. It basically made my left knee unable to bend. It took an MRI to diagnose and arthroscopic surgery to remedy. I was about thirty when it happened and I feel like it was induced by an injury even though those types of cysts can happen at any time.
You really need to go to the doctor.

I have a Baker’s cyst, though it hasn’t flared up in ten years. My doctor says the issue could be resolved with a simple operation, but since it’s not negatively affecting me I shouldn’t bother at this time.

I do take care to make sure my knees aren’t bent for long periods. I can recognize a burning sensation before it gets bad (unless that’s psychosomatic).

You should absolutely see a doctor to make sure this is nothing serious.

Doctor time. The wrong treatment could make it worse. Get a proper diagnosis.

If that’s really what it is you need the doctor anyway for treatment, so get this confirmed with a qualified person.
Then find a doctor who can work with ultrasound while poking a draining needle into it;
Seems like more and more doctors can operate the ultrasound themselves than used to, or have staff in the office that do that while the needle is inserted. The ultrasound gives the doctor info to optimize the entry point and to monitor how completely drained it is.