We pretty much ditched the entirety of the IBM provided relevance and simply went with checking the registry uninstall string:
(windows of operating system) AND (exists keys whose (value “DisplayName” of it as string as lowercase contains “firefox” of it AND value “DisplayVersion” of it as string as version < “60.0”) of keys “HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall” of (x64 registries; x32 registries))
The actionscript doesn’t account for a situation that exists where someone has both a 64bit and 32bit installation and fails in testing, but I decided to deal with that on a case by case basis since it should largely be non-existent (assumptions I know, but so far so good).
A lot of machines were returning not-relevant due to
exists key whose (name of it as lowercase starts with “mozilla” AND exists key whose (name of it = “Mozilla Firefox”) of it) of key “HKLM\SOFTWARE” of registry
Which was included in the IBM fixlet.