Moving a tree to a new window circumvents VimFx in all moved tabs except the root tab

[braham-snyder]

Short description

Moving a tree of tabs to a different window seems to prevent VimFx commands from working in the moved tabs, except for the root tab. I'm encountering this behavior when using any of the following methods to move a tab tree to a new window: the "Move to New Window" item in the tab context menu; dragging and dropping the root tab--either to a different, existing window, or away into a new window; VimFx's "Move to New Window" command¹, gw.

Steps to reproduce

1. Start Firefox with clean profile.
2. Install TST
3. Install VimFx
4. Open a child tab (e.g., in the root tab, google something, then open a result link in a child tab with F)
5. Move the root tab (and its child tab) to a different window (using any of the techniques mentioned above, e.g., right click the root and hit "Move to New Window")

Expected result

The moved tabs respond to VimFx commands as they did before movement to the new window (e.g., J and K allow one to cycle forward/backward among the tabs).

Actual result

Only the root of the moved subtree responds to VimFx commands--the remaining tabs behave as if VimFx was not installed (e.g., no errors in the browser console).

Environment

• Platform (OS): OS X El Capitan
• Version of Firefox: 52.0 (64-bit)
• Version (or revision) of Tree Style Tab: 0.19.2017031101

Thank you for TST!!

¹ Here's that VimFx command's source code:

commands.tab_move_to_window = ({vim}) ->
  {gBrowser} = vim.window
gBrowser.replaceTabWithWindow(gBrowser.selectedTab)

[braham-snyder]

closing due to Firefox's sunsetting of XUL