Add-on missing during remote debugging

[basiphobe]

The aXe add-on is not available using Firefox's remote debugging feature. The add-on is installed (and working correctly) both locally, and on the remote instance, and is listed under the "Available remote add-ons" after connecting remotely. But choosing the aXe option results in the developer tools window displaying an error:

Could not map contract ID '@mozilla.org/widget/printdialog-service;1' to CID {06beec76-a183-4d9f-85dd-085f26da565a} because no implementation of the CID is registered.

Remote Firefox is running in a Virtualbox VM. Local Firefox (61.0b4 (64-bit)), and remote Firefox (60.0 (64-bit)) are both running under Windows 10. All other remote debugging tools (inspector, console, etc.) are working as expected.