The bug is that when you copy bolded-colored text from an eshell buffer into an enriched-text buffer, the bold shows after the copy --- but if you then close the enriched-text file, and re-open it, the bolding is gone.

(1) emacs -Q

(2) M-x eshell

(3) cd /etc

(4) ls

(5) control-X 2

(6) scroll up a dozen lines using control P; then type escape-w to capture the text

(7) find-file /tmp/blah.txt

(8) yank in the captured text (control-y)

(9) M-x enriched-text  (so make /tmp/blah.txt into an enriched text file)

(10) kill the buffer (control-x k)

(11) reopen the file (find-file)

(12) observe that although the colors are still there, the bolding is gone.