wilhelmmedetz See also: https://forum.legendapp.com/d/372-how-to-get-the-tag-view/13
It doesn’t get changed into a heading unless you type a space after the #. Also, you can simply type a tag at the beginning of a line; the problem is that the tag-picker popup won’t function correctly.
For your workaround, if you want to use the tag-picker popup, you’d actually need to enter two spaces, then left-arrow, enter the tag, then go back and delete the first space. If you don’t need to use the tag-picker, you can just go ahead and type the tag, followed by a space.
Another workaround, if you need the tag-picker, that may be a couple less keystrokes, is to press enter at the beginning of the line, enter the tag and a space, then right-arrow and backspace to combine the lines.