I’ve had some puzzling loss of outline structure in TaskPaper files that have been moving back and forth macOS TaskPaper ⇄ iOS Drafts 5.
It turns out that there was a problem with using the standard Indent and Outdent actions distributed with Drafts5 if you use them in the Drafts5 TaskPaper mode, and existing TaskPaper tab-indents could get invisibly intermingled with Drafts-injected four-space indents.
TaskPaper 3 does a pretty good job of catching space-indented outlines (TaskPaper is, of course, a tab-indented outline format) but some permutations of mixed indents in the same line can be a problem, and structure which you thought you had added in Drafts turns out not to be there.
Agile Tortoise has now fixed a couple of bugs (mode-insensitive space-indenting, and overextension of selection on outdent) in the Indent-Outdent action pair, and the newer (editing-mode sensitive) versions are online at:
You will, however, need to manually delete the existing actions, and replace them with these new copies – the current update model of Drafts is that installed actions are not updated when the app is updated, even after bugs have been found.
(FWIW I’ve personally gone back to using 1Writer on iOS – its model and file management fits my work a bit better, and the indent and outdent are built in, and can be relied on to work with tabs. Like Drafts, it is also JS-scriptable)