Thread:AnonymousPvZFan23/@comment-29637681-20180622232032/@comment-29637681-20180624025158

If you use a Mobile device, it will always be set to Source mode.

If you use a Desktop, it's usually set to Visual Editor. This is signified by two icons next to the Bold, Italics, and Link buttons at the bottom of the editor. Clicking the brackets "[ ]" takes you into Source mode.

Best I can explain it.