1) document: constraints for video reverse
2) document: Shift + LMB to delete brush, Shift + LMB to switch character sets
3) feature: allow to adjust cutoff warning threshold, {dis,en}able cutoff & print line numbers affected
4) feature: {bold,italic,underline} attributes
5) feature: keyboard instead of [LR]MB
6) feature: {line,measuring} tool
7) feature: status bar w/ position, etc.
8) feature: zoom {in,out}
9) reimplement: {save,upload} as PNG & gallery