X.L.StateFull's `FocusTracking` and the eponymous `TrackFloating` were
redundant, hence the former was slated for deprecation. However,
the latter and its host module are somewhat poorly named; the layout
modifier has little relation to floats. As such, it's renamed and
rehosted, becoming the eponymous `FocusTracking`.
The redundant offerings in the original modules are redefined in terms
of the new module where possible, and deprecated.
See: #418; comments on #253, #783.
This is a convenience module in order to have less import noise. It
re-exports the following:
a) Commonly used modules in full (Data.Foldable, Data.Applicative, and
so on); though only those that play nicely with each other, so that
XMonad.Prelude can be imported unqualified without any problems.
This prevents things like `Prelude.(.)` and `Control.Category.(.)`
fighting with each other.
b) Helper functions that don't necessarily fit in any other module;
e.g., the often used abbreviation `fi = fromIntegral`.
When focus changes¹ on an inactive workspace (not `current`, but
`visible`), TrackFloating and UseTransientFor would think they should
use the remembered focus point as they look at the wrong (`current`)
workspace instead of the workspace they're supposed to layout, and so
focus seems to be out of their set of windows, when actually it is not.
Fix this by looking at the correct workspace.
¹) This isn't entirely straightforward, as there are normally no
keybindings or StackSet operations for this, but it's perfectly legal
to `W.view` the inactive workspace, change focus, and `W.view` back
in a single `windows` action.
It was added in 81d338952d in an attempt to fix focus handling after
closing a floating window, but shortly after made redundant in
a551d1367c when we noticed it causes more harm than good. Unfortunately
it wasn't fully reverted, making the code more complex than necessary.
Drop the remaining bits.
Now it's almost obvious that the only difference between this and
X.L.StateFull.FocusTracking is the isF condition.
BTW the original issue 81d338952d was trying to fix can be fixed by
using X.H.RefocusLast, from the author of X.L.StateFull.FocusTracking.
:-)
Now TrackFloating remembers focus for the given layout when the other window is
also tiled, but not fed to the given layout: this helps with X.L.IM, among
others.
Addresses the comment that:
If the focus goes from the floating layer to tiling by deleting a floating
window, it's again the master window that gets focus, not the remembered
window.
