According to Microsoft, installed browsers must register under one of the following keys:
HKEY_CURRENT_USER\SOFTWARE\Clients\StartMenuInternet\
HKEY_LOCAL_MACHINE\SOFTWARE\Clients\StartMenuInternet\
HKEY_LOCAL_MACHINE\SOFTWARE\WOW6432Node\Clients\StartMenuInternet\
Here you can find the "Browser name" under "Capabilities\ApplicationName", the "Default icon" under "DefaultIcon" and the "Path to executable" under "shell\open\command"
The only browser that doesn't follow the guidelines is Internet Explorer, which is missing the "Capabilities" key