Quote selected text: button is not shown when selecting entire post

[live627]

from https://www.simplemachines.org/community/index.php?topic=579109.msg4099001#msg4099001

1. About a third of a time, the Quote Selected Text button does not appear, regardless of whether the text is selected from beginning to end, or end to beginning. A few members have had this issue. Sometimes I'll have to highlight text 3 or 4 times to get the button to appear.

To reproduce, select a post to quote but be sloppy, purposefully selecting either the time, the post bit, or both. Or even another post.