Hi Sergej,
Thanks a lot for your article as it helped me fix several issues I've been struggling with for hours when trying to use to the 'docker image for SPFx 1.15.0' (https--hub.docker.com/r/m365pnp/spfx/) on Windows 10.
As I'm new to docker (with WSL 2), I had a first issue (not mentioned in your article) to copy and install the trusted dev certificate:
But that was not enough as I bumped into the 2nd issue dealing with the web part not available in the workbench (same problem as you mentioned in your article). Although that's a known issue with >=1.14.0 as reported on the 'docker m365pnp/spfx page' (https--hub.docker.com/r/m365pnp/spfx/), the proposed fix simply doesn't work (the ipAddress attribute does not exist)! After many tryouts, both fixes for 1.13.1 still applies:
After these changes, the web part appears and run correctly in the workbench.
Note: sorry for the links but I could not include any url in my comment (as I'm new Hashnode user) :-(