Odd occurance when editing a note

Windows 10, RM I just tried to copy some text from an external source and paste it into a fact note. That worked fine, but I knew the text was missing the first character when I copied it. So, I went to the top of the note and put my cursor before the first character of the first line in order to add the missing letter. When I tried to add the letter, it did not appear in the intended place. It appeared at the end of the first line on the right hand side. I tried to add the letter several times with the same result. Then I saved the note, exited the note and re-edited it to see if I could add the letter and it worked correctly this time.