• [varLib.models] Reverted PR #2717 which added support for "narrow tents" in v4.36.0, as it introduced a regression (#2764, #2765).
  It will be restored in upcoming release once we found a solution to the bug.
• [cff.specializer] Fixed issue in charstring generalizer with the blend operator (#2750, #1975).
• [varLib.models] Added support for extrapolation (#2757, #671).
• [ttGlyphSet] Ensure the newly added _TTVarGlyphSet inherits from _TTGlyphSet to keep backward compatibility with existing API (#2762).
• [kern] Allow compiling legacy kern tables with more than 64k entries (d21cfde).
• [visitor] Added new visitor API to traverse tree of objects and dispatch based on the attribute type: cf. fontTools.misc.visitor and fontTools.ttLib.ttVisitor. Added fontTools.ttLib.scaleUpem module that uses the latter to change a font's units-per-em and scale all the related fields accordingly (#2718, #2755).