Normally I would assume that these changes, being downstream of where Firefox and Pale Moon parted company, can safely be ignored. But this sounds like a significant change, potentially to an underlying service or standard, that may affect the shared underpinnings of the two browsers to the extent that extensions are no longer intercompatible. In an unlikely worst-case scenario, it may lead to the current catalogue of Firefox-based extensions being updated (either en bloc or piecemeal) to a form no longer compatible with Pale Moon, and support for the compatible 'legacy' versions being discontinued.
Any advice would be useful. I'm in an awkward state of knowledge: enough to realise that something might be an issue, but not enough to know whether it actually is or not!
Text of popup:
Tile Tabs - Important Notice
Tile Tabs will not work with Firefox 57 or later
Tile Tabs was developed using technologies that are no longer available in Firefox 57.
Firefox 57 will be released on 14 November 2017.
Tile Tabs WE is the replacement for Tile Tabs
Tile Tabs WE has been developed using the new Web Extensions API's.
Tile Tabs WE is available for both Firefox (48 or later) and Chrome (35 or later).
You can download Tile Tabs WE for Firefox from:
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