Header Tools Improved

Z 5 z 5 gwězdkow pógódnośony

wót Wužywaŕ Firefox 2fab74 dnja Jan. 13, 2025 · trajny wótkaz

[This is more a question than a review, but I can't find other means of contacting the developer. Five stars on the basis of my earlier experience with HTI!]

I've installed HTI in the latest version of Thunderbird (actually, Thunderbird Portable, if this makes any difference). If I use either the context menu or the hotkeys I've set up, HTI does seem to activate, since if I invoke the edit source function the warning message displays. However after clicking on OK or opting for editing headers only, nothing more happens. No window pops up to allow editing. Am I missing something? Could using Thunderbird Portable somehow cause the problem?