That’s a bug that’s fixed in testing releases that came out after 2.1.0.5. You can try:

Is there still no solution for the trayicon when installed as a service?
There’s a solution (Canary test release), and messy workaround. No new Stable. Unlike 2.1.0.5 which solved severe issues in 2.1.0.4, this issue seems “less” hot, because it can be worked around. Maybe the dev will forecast next release plan?
Previous one looked like a hotfix release. I hope next one has longer testing time, although admittedly that testing gets in the way of getting it released more quickly.