"Start profiling" Button needs capitalisation. Also the blue styled version if it’s the default button for this dialog.
Fixed in version 188.8.131.52 (master)
Author: Rodrigo Moya
Commit: 73d0661568d2087be73e89f92cd3c7331c431abe (xamarin/profiler)
I have checked this issue with Profiler v1.1.99-124(Master) and 1.0.4-9(C8SR1) and observed that "Start profiling" Button still showing in lower case.
Here is the screencast for the same.
Correcting C8SR1 build as shown in C8SR1 screencast.
Build Info: Profiler v1.0.4-10
As discussed with @Rodrigo Profiler's P has been set to Capital. So changing status to verified.