Currently, the ‘Convert to To-do’ option only adds a checkbox in front of the title of the note. What it should do is add a checkbox at the start of every line with text. Thus converting the note into a complete to-do list.
You’re misunderstanding what a todo is in Joplin. A todo in Joplin is a not with a checkbox in front of it that can have an optional todo date (complete with an alarm). This is a frequently used feature of Joplin and will not likely be removed.
What you’re looking for instead is this button. Or on mobile I believe autocompleting checkboxes will work eventually (which should answer your other forum post)
Yeah, you’re right. I misunderstood. Sorry.