Thank you for your requests!
We are already thinking to specify the version, under which the code is tested. This will happen in our Developers Manual as well, probably starting from the next release.
The Extensionless functionality is already available, the only thing we are missing is a master switch (something like enabled/disabled). Actually, to make this work, you need to change some settings manually in IIS as well, so I am not sure if it will be possible to have that kind of setting in UI.
For more information about this, please refer to our User Manual, and the topic Extensionless URLs.
All the best,
the Telerik team
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