Firefox 57.0a1 (2017-08-06) breaks Keysnail

[jbeich]

Keysnail bindings no longer work after bug 1375125.

Steps to reproduce

1. Install Firefox Nightly build 20170806100257 or later
2. Allow legacy/non-mpc extensions per wiki
3. Install Keysnail
4. Create ~/.keysnail.js with Emacs/w3m keybindings
5. C-t (Open new tab)
6. C-x k (Close tab)
7. C-x C-c (Close browser)

Actual result

6 and 7 steps do nothing

Expected result

6 and 7 do desired actions

Workaround

Locally revert mozilla/gecko-dev@06311d2, switch to Beta 56 or ESR52

Browser console

KeySnail.initModule :: [Exception... "Component returned failure code: 0x80570018 (NS_ERROR_XPC_BAD_IID) [nsIJSCID.createInstance]"  nsresult: "0x80570018 (NS_ERROR_XPC_BAD_IID)"  location: "JS frame :: chrome://keysnail/content/modules/util.js :: openFile :: line 171"  data: no]
[Exception... "Component returned failure code: 0x80570018 (NS_ERROR_XPC_BAD_IID) [nsIJSCID.createInstance]"  nsresult: "0x80570018 (NS_ERROR_XPC_BAD_IID)"  location: "JS frame :: chrome://keysnail/content/modules/util.js :: openFile :: line 171"  data: no]  (unknown)

[jbeich]

Also, bug 1387009 a few days before broke select_(next|previous)_tab (C-M-l/r or l/r for Emacs-style) and close_all_tabs_on_(left|right).

[Inops]

It might be an idea for someone to make the necessary changes to allow KeySnail to work out-of-the-box with Pale Moon. It complains about being "not compatible" with Pale Moon, but after installing an extension to prevent compatibility checks, it works as expected. Pale Moon isn't dropping XUL extension support, so perhaps this is a good way for KeySnail to live on, without necessitating a massive (and less powerful) rewrite.

[phil-s]

For Pale Moon I copied my ~/.mozilla/firefox/(profile)/extensions/keysnail@mooz.github.com directory into to ~/.moonchild productions/pale moon/(profile)/extensions/ and edited its install.rdf file and, based on the GUID listed at https://forum.palemoon.org/viewtopic.php?p=55987#p55987 , changed the target application element to:

    <!-- Pale Moon -->
    <em:targetApplication>
        <Description>
            <em:id>{8de7fcbb-c55c-4fbe-bfc5-fc555c87dbc4}</em:id>
            <em:minVersion>25.*</em:minVersion>
            <em:maxVersion>99.*</em:maxVersion>
        </Description>
    </em:targetApplication>

After restarting Pale Moon I was able to enable KeySnail.