If you have projects in different languages you can set different LSPs.
The default will still come from ~/.teco_ini if you decide to set one.
The default for $SCITECO_LSP_ROOT is set by session.tes' VCS integration
based on the VCS root, but you could still overwrite it per session.

* The main interface is the `FT` command.
  `FT` was an undocumented Video TECO command for etags/ctags lookups.
  I don't want to exactly copy its interface, though.
* `FT` allows looking up symbol names,
  definitions and references.
* ctags will be supported via ctags-lsp.
  LSP support is more powerful though and works without
  regenerating TAGS files all the time.
  The LSP will also allow you to customize auto-completions
  using SciTECO itself (i.e. by writing a language server
  in SciTECO).
* For multiple results, `FT$` can be used to cycle through
  results - this should mimic repeated `S$` or `N$`.
* `:FT...$` does a fuzzy search. IMHO it's not important
  to return a status integer instead. `FT` will only
  really be used in interactive mode.
* Document synchronization is supported via hooks from
  ring.c and via Scintilla notifications.
* Currently, the LSP communication is based on blocking
  GIOChannels. This means that a misbehaving hanging
  server could "lock up" the entire editor (FIXME).
  Only on ncurses you can always kill the subprocess by
  pressing CTRL+C.
  We need helper functions in spawn.c to read and write
  with interruptions.
* The textDocument/didChange notification transmits
  not only all edits, but all files' contents as well
  during initial synchronization.
  Therefore it is optimized to write and JSON-escape
  data without copying them around in memory and without
  destroying the buffer gap.
* Use $SCITECO_LSP to configure the language server.
  You can also use `tee` to capture stdin and stdout.
  Perhaps $SCITECO_LSP should be saved in .teco_session,
  so you can change it between projects?
* $SCITECO_LSP_ROOT is used to point to the project's
  root directory. session.tes will set it up automatically.

It will be useful for implementing LSP support.
It does not have JSON escape/unescape functions, so those
will still have to be written.

Source: https://github.com/rxi/sj.h

This is useful when writing small macros directly on the
command-line as in `sciteco --eval`. If you use double quoted shell
strings, too many characters have to be escaped.
If you use single-quotes, though, embedding the conditional end (')
is annoying -- it would have to be written as '\''.

Inlining the macro calls no longer results in a 25% speedup.

This for the first time mentions all of the bundled core libraries
in the end user documentation.

* Allows searching by regular expressions.
  We will never support all ARE constructs in TECO patterns, so this is useful to have available.
* Can only be typed upcaret.
  This leaves ^E~q available as an escape-regexp string building construct.
* Once we replace the pattern2regexp converter with a custom terex lexer,
  we might want to restrict ^~ to the beginning of the pattern.
  Currently, however it can be anywhere, so you can mix TECO patterns with regular expressions.

* The terminal's default foreground and background colors
  are now used by default (`sciteco --no-profile`), so SciTECO
  integrates naturally into all terminal color schemes, even
  dark-on-bright ones.
* The default Scintilla colors use only 0x000000 (COLOR_BLACK) and 0xC0C0C0 (COLOR_WHITE)
  now.
* You can use `7EJ` to configure the default colors in color
  schemes or your profile.
  All existing color schemes had to disable default colors
  (`-1,-1,7EJ`) since they wouldn't look well otherwise.
* You may add `-1,7EJ` to ~/.teco_ini when using a terminal emulator
  with a washed-out palettized COLOR_BLACK.
  We cannot detect the terminal's default colors automatically.
* Scinterm updated to v6.0.
  We require a not-yet-upstreamed patch:
  https://github.com/orbitalquark/scinterm/pull/40
* In fact, we might decide not to support default colors at all in Scinterm,
  so this feature should be considered experimental.

* SIGTERM used to insert the ^KCLOSE key macro.
  However with the default ^KCLOSE macro, which inserts `EX`,
  this may fail to terminate the editor if buffers are modified.
  If the process is consequently killed by a non-ignorable signal,
  we may still loose data.
* SIGTERM is used to gracefully shut down, so we now always terminate.
  Since we have recovery files, they are now dumped before terminating.
  This makes sure that recovery files are more up-to-date during
  unexpected but gracefull terminations.
* The same functionality is planned on Curses, but requires more fundamental
  changes (TODO).