Operating system: Windows-10-10.0.17134 64 Bits
Graphics card: GeForce GTX 1080/PCIe/SSE2 NVIDIA Corporation 4.5.0 NVIDIA 431.36
Broken: version: 2.80 (sub 74), branch: master, commit date: 2019-07-18 14:52, hash: rB38d4483c6a51
Short description of error
When there is more than one particle system on an object the name of the selected particle system won't update in the top of the Properties Panel until the mouse is hovered over the title.
Exact steps for others to reproduce the error
Based on the default startup or an attached .blend file (as simple as possible).
With the default cube selected, go to the Particles section of the Properties Panel and add two new particle systems. Select the first particle system again and the top of the Properties Panel "Cube > ParticleSettings.001" won't change to "Cube > ParticleSettings" until the mouse hovers over any of that text. Same if you re-select ParticleSettings.001, it won't update the name until the mouse moves over the text at the top of the Properties Panel.