Editing text in place with the document’s real font was the feature the owner named first, and it is the one no free library does. The plan split it in two, and the first half is in: find the text, select it, and find the font. Only once the fonts can be found with confidence does the second half write anything into a PDF.
What is in
A text model for each page, built from what the engine reports; selection of that text in Edit mode; and a matcher that takes each font the document uses and looks for it among the fonts installed on the machine. This is the groundwork for the rule set at planning: an edit in a font the machine does not have is refused until the owner picks one, with help.
Review
One round. The reviewer found that fonts with no typographic family name, a common case among older faces, were reported as not installed when they were. The matcher now compares on the font’s PostScript name, which every font carries.
A rule confirmed
Fonts carry embedding rights that say whether they may be written into a document at all. Those rights are enforced in the save path, in the core, not only in the interface. A window that forgets to check cannot produce a file that breaks a font’s licence.
Next: the second half, editing the text and saving it back.