Looking at the documentation we are seeing that the crossbrowsertesting tool support various Operating systems and thus corresponding browsers as mentioned in the below link
https://crossbrow...
The CrossBrowser integration with TestComplete runs automated tests on the actual devices in the CrossBrowserTesting cloud space using a copy of test execute spun up to do so. TestExecute will not run on MacOS or Ubuntu not can it be installed on Android or iOS devices. While CrossBrowserTesting.com supports those operating systems in the direct live tests available in CBT, the integration with TestComplete is limited.