Update the FAQ on vim with a comprehensive set of settings needed to get it to work with modern terminals

docs/faq.rst

@@ -27,17 +27,70 @@ turned off for specific symbols using :opt:`narrow_symbols`.
 Using a color theme with a background color does not work well in vim?
 -----------------------------------------------------------------------
 
-First make sure you have not changed the :envvar:`TERM` environment variable, it
-should be ``xterm-kitty``. vim uses *background color erase* even if the
-terminfo file does not contain the ``bce`` capability. This is a
-`bug in vim <https://github.com/vim/vim/issues/11716>`__. You
-can work around it by adding the following to your vimrc::
+Sadly, vim has very poor out-of-the-box detection for modern terminal features.
+Furthermore, it `recently broke detection even more <https://github.com/vim/vim/issues/11729>`__.
+It kind of, but not really, supports terminfo, except it overrides it with its own hard-coded
+values when it feels like it. Worst of all, it has no ability to detect modern
+features not present in terminfo, at all, even security sensitive ones like
+bracketed paste.
 
+Thankfully, probably as a consequence of this lack of detection, vim allows users to
+configure these low level details. So, to make vim work well with any modern
+terminal, including kitty, add the following to your :file:`~/.vimrc`.
+
+.. code-block:: vim
+
+    " Mouse support
+    set mouse=a
+    set ttymouse=sgr
+    set balloonevalterm
+    " Styled and colored underline support
+    let &t_AU = "\e[58:5:%dm"
+    let &t_8u = "\e[58:2:%lu:%lu:%lum"
+    let &t_Us = "\e[4:2m"
+    let &t_Cs = "\e[4:3m"
+    let &t_ds = "\e[4:4m"
+    let &t_Ds = "\e[4:5m"
+    let &t_Ce = "\e[4:0m"
+    " Strikethrough
+    let &t_Ts = "\e[9m"
+    let &t_Te = "\e[29m"
+    " Truecolor support
+    let &t_8f = "\e[38:2:%lu:%lu:%lum"
+    let &t_8b = "\e[48:2:%lu:%lu:%lum"
+    let &t_RF = "\e]10;?\e\\"
+    let &t_RB = "\e]11;?\e\\"
+    " Bracketed paste
+    let &t_BE = "\e[?2004h"
+    let &t_BD = "\e[?2004l"
+    let &t_PS = "\e[200~"
+    let &t_PE = "\e[201~"
+    " Cursor control
+    let &t_RC = "\e[?12$p"
+    let &t_SH = "\e[%d q"
+    let &t_RS = "\eP$q q\e\\"
+    let &t_SI = "\e[5 q"
+    let &t_SR = "\e[3 q"
+    let &t_EI = "\e[1 q"
+    let &t_VS = "\e[?12l"
+    " Focus tracking
+    let &t_fe = "\e[?1004h"
+    let &t_fd = "\e[?1004l"
+    execute "set <FocusGained>=\<Esc>[I"
+    execute "set <FocusLost>=\<Esc>[O"
+    " Window title
+    let &t_ST = "\e[22;2t"
+    let &t_RT = "\e[23;2t"
+
+    " vim hardcodes background color erase even if the terminfo file does
+    " not contain bce. This causes incorrect background rendering when
+    " using a color theme with a background color in terminals such as
+    " kitty that do not support background color erase.
     let &t_ut=''
 
-See :doc:`here <deccara>` for why |kitty| does not support background color
-erase.
-
+These settings must be placed **before** setting the ``colorscheme``. It is
+also important that the value of the vim ``term`` variable is not changed
+after these settings.
 
 I get errors about the terminal being unknown or opening the terminal failing when SSHing into a different computer?
 -----------------------------------------------------------------------------------------------------------------------