Why Did Mozilla Remove XUL Add-ons?
Why Did Mozilla Remove XUL Add-ons?
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TL;DR: Firefox used to have a great extension mechanism based on the XUL and XPCOM. This mechanism served us well for a long time. However, it came at an ever-growing cost in terms of maintenance for both Firefox developers and add-on developers. On one side, this growing cost progressively killed a...
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An old article but provides a detailed view on the choice of removing the old XUL addons