v2.221

• Tuned Vietnamese diacritics more, removed errors in Ẫ
• Removed 0x0 ligature #346
• Added ⟵ ⟷ ⟶ #255
• Corrected vertical placement on BoxDrawing elements
• Removed .- ligature #76
• Disabled ligatures for lookahead/lookbehind prefixes (regex) #126
• Added support for combined marks #228
• Added ∪ #244
• Added ➜(U+279C), ✗(U+2717), and ✓(U+2713) #246
• Added <<~ #291
• Added ‾ Overline #298
• Tuned Cyrillic в #335
• Increase height of BoxDraving #382
• Added ‿ ∁ ∎ ⊸ ⊎ ⨀ ⨆ ∩ ∶ ⊢ ⊤ ⊥ ⊛ ⊖ ⊗ ⊙ ⊕ ◦ ⋆ ℚ ℤ slashshortcomb
• Corrected placement of bar in Đ
• Polished Digits