PeachPDF applies a font's real GSUB liga/clig ligature substitution (not a synthesized effect) - font-variant-ligatures: none turns it back off. Source Sans 3's liga feature merges "ff"/"ft"/"fft" into single connected glyphs.
| word | default (ligated) | font-variant-ligatures: none |
|---|---|---|
| office | office | office |
| soft | soft | soft |
| offset | offset | offset |
A gradient/pattern fill outlines each glyph to a vector path instead of showing text (see Text & Fonts → SVG support) - ligature shaping applies to that outlined path the same way it applies to ordinary text.