Form History Control end-of-life?

As much as I like to further develop the FHC add-on, the upcoming changes by Mozilla make it very difficult, if not impossible, to keep this add-on compatible with future versions of Firefox.

The changes needed to make FHC multiprocess (aka Electrolysis or e10s) compatible are surely possible and probably not very hard to do (although it does probably take many, many hours of work to implement), but the changes needed to make it WebExtensions compatible and maintain it's current features are almost certainly impossible.

The API's supported by WebExtensions do not include an API for accessing the formhistory which is the base for one of the core features of this add-on.
Furthermore this add-on relies heavily on XUL for the GUI and that is also gone under WebExtensions, so the complete GUI and all its interactions have to be rewritten from scratch.

According to the timeline of mozilla, it looks like WebExtensions are becoming the standard for add-on development in Firefox and will be the only type of add-on supported in Firefox by the end of 2017. (see wiki.mozilla.org and blog.mozilla.org)

All things considered I have to conclude that this Form History Control add-on has come end-of-life.

Showing formhistory data gathered by the browser itself (for auto-completion) was originally the main purpose of this add-on and it seems like this data will no longer be available to add-ons, so hopefully at some point in time this will be built into the browser itself by Mozilla. Maybe, if I can find the time and inspiration, I will start building a new add-on that supports (re)storing formhistory data from textfields and editor-fields since this feature has often been very useful for me too.