SUMMARY
When using the Gradient Tool I can change the Opacity slider. This setting is stored in the active brush, so each brush is able to remember its own Gradient Tool Opacity.

When switching the brush while in the Freehand Brush Tool, and then using the Gradient Tool, 
the Opacity for the Gradient Tool will be forgotten on the other brushes. 

This leads to frequent resetting of the Gradient Opacity to 100 percent. This is not ideal.

STEPS TO REPRODUCE
1. Switch to the gradient tool
2. Change the opacity to 20 percent
3. Switch to the freehand brush tool and then to a different brush
4. Switch to the gradient tool
5. Switch back to the freehand tool and switch back to the original brush
6. Switch back to the gradient tool.

OBSERVED RESULT
The gradient opacity easily gets reset to 100 percent on brushes.

EXPECTED RESULT
The gradient opacity should be remembered, for the brushes.
Ideally the gradient opacity should be kept consistent across all brushes, as if the setting is stored in the tool itself.

SOFTWARE/OS VERSIONS
  Build ABI: x86_64-little_endian-lp64
  Build CPU: x86_64
  CPU: x86_64
  Kernel Type: linux
  Kernel Version: 5.15.0-56-generic
  Pretty Productname: Ubuntu 22.04.1 LTS
  Product Type: ubuntu
  Product Version: 22.04
  Desktop: XFCE

ADDITIONAL INFORMATION

Version: 5.2.0-prealpha (git 0351bde)
Hidpi: false