This is a big one. Holidays and all. Wishing all of you the best for 2022! See the note below about theme changes if you're super picky about your theming.

New Languages:

• Added 3rd party Pine Script grammar to SUPPORTED_LANGUAGES Jeylani B
• Added 3rd party cURL grammar to SUPPORTED_LANGUAGES highlightjs-curl

Themes:

• Default is now much closer WCAG AA (contrast) (#3402) Josh Goebel
• Dark now meets WCAG AA (contrast) (#3402) Josh Goebel
• Added intellij-light theme Pegasis

These changes should be for the better and should not be super noticeable but if you're super picky about your colors you may want to intervene here or copy over the older themes from 11.3 or prior.

Grammars:

• enh(arcade) updated to ArcGIS Arcade version 1.16 John Foster
• enh(php) Left and right-side of double colon Wojciech Kania
• enh(php) add PHP constants Wojciech Kania
• enh(php) add PHP 8.1 keywords Wojciech Kania
• fix(cpp) fix vector<< template false positive (#3437) Josh Goebel
• enh(php) support First-class Callable Syntax (#3427) Wojciech Kania
• enh(php) support class constructor call (#3427) Wojciech Kania
• enh(php) support function invoke (#3427) Wojciech Kania
• enh(php) Switch highlighter to partially case-insensitive (#3427) Wojciech Kania
• enh(php) improve namespace and use highlighting (#3427) Josh Goebel
• enh(php) $this is a variable.language now (#3427) Josh Goebel
• enh(php) add __COMPILER_HALT_OFFSET__ (#3427) Josh Goebel
• enh(js/ts) fix => async function title highlights (#3405) Josh Goebel
• enh(twig) update keywords list (#3415) Matthieu Lempereur
• fix(python) def, class keywords detected mid-identifier (#3381) Josh Goebel
• fix(python) Fix recognition of numeric literals followed by keywords without whitespace (#2985) Richard Gibson
• enh(swift) add SE-0290 unavailability condition (#3382) Bradley Mackey
• fix(fsharp) Highlight operators, match type names only in type annotations, support quoted identifiers, and other smaller fixes. Melvyn Laïly
• enh(java) add sealed and non-sealed keywords (#3386) Bradley Mackey
• enh(js/ts) improve CLASS_REFERENCE (#3411) Josh Goebel
• enh(nsis) Update defines pattern to allow ! (#3417) idleberg
• enh(nsis) Update language strings pattern to allow ! (#3420) idleberg
• fix(stan) Updated for Stan 2.28 and other misc. improvements (#3410)
• enh(nsis) Update variables pattern (#3416) idleberg
• fix(clojure) Several issues with Clojure highlighting (#3397) Björn Ebbinghaus
  • fix(clojure) comment macro catches more than it should (#3395)
  • fix(clojure) $ in symbol breaks highlighting
  • fix(clojure) Add complete regex for number detection
  • enh(clojure) Add character mode for character literals
  • fix(clojure) Inconsistent namespaced map highlighting
  • enh(clojure) Add regex mode to regex literal
  • fix(clojure) Remove inconsistent/broken highlighting for metadata
  • enh(clojure) Add punctuation mode for commas.
• fix(julia) Enable the jldoctest alias (#3432) Fons van der Plas

Developer Tools:

• (chore) add gzip size compression report (#3400) Bradley Mackey

Themes:

• Modified background color in css for Gradient Light and Gradient Dark themes Samia Ali