adjust scribble lexer so its failures print to stderr, not stdout
unbreak scheme-lexer
don't save repl interaction history when the new item is
a duplicate of the one before

closes PR 12763
improve the interactions history window a little
esc;h history note
fix the c:x;n keybinding when used with online check syntax info

 (and perhaps other parts of online check syntax)
add a 'jump to previous binding occurrence' keybinding
Add testcases for many already fixed bugs.

Closes PR11901.
Closes PR11972.
Closes PR12022.
Closes PR12224.
Closes PR12506.
Closes PR12533.
Closes PR12596.
Closes PR13198.
Closes PR13418.

Already fixed bugs, with existing testcases.
Closes PR12529.
Closes PR12631.
Closes PR13127.
Closes PR13128.
Closes PR12970.
Improve types for exit and in-naturals.
Improve type of make-immutable-hash.

Closes PR13297.
Fixes *-filter types and filter of zero?.

Closes PR13275.
configure: add more guidance/reporting on non-recommended options
ffi/unsafe: fix a bug in conversion to UTF-16

Characters outside of the BMP were translated incorrectly.
JIT: fix bug in checking certain values before unboxing

The check was incomplete in the case that both arguments to a binary
[ext]flonum function need to be checked and the second one was not an
[ext]flonum and also not a fixnum.
scribble: preserve order of ".js", ".css", and ".tex" additions
add parameterize* to tabing and smart opening square bracket pref defaults
interactivity fix for online check syntax

commit e503850f21aab20234f580c9e14c7e3764383e80 broke drracket's
interactivity (for some files it could take 2 seconds to do
that one line)

This changes the bindings-table so that it maps to sets instead of
lists. Now, instead of mutating all entries in the table right after
collecting everything, just leave them as sets until we need the info
and just sort a single entry, when it is needed
ffi/unsafe: add `_size', `_ssize', `_ptrdiff', `_intmax', `_uintmax'

These additions could create backward-compatibility problems, but our
searches suggest that problems will be rare; it's more common for
`_size_t' to be incorrectly aliased to `_int', so having definitions
for these standard types is likely to avoid future problems.
racket/base: add `impersonator-ephemeron'
racket/snip: fix `style-list%' `notify-on-change' and contracts

The method uses the new `impersonator-ephemeron' function to
retain a callback as long any value that it impersonates
is reachable.