This does not copy the file. I am owner of both directories.
And there are no messages?
cd /home/andy/.mozilla/seamonkey/4e39n1np.default/
cp -f bookmarks.html /home/andy/.mozilla/firefox/mltw8z53.default-1516629000620/
File exists. File can't be moved in file explorer. I even deleted the "Firefox bookmarks file" and copied Seamonkey bookmarks file there??
Adding the output of namei -
f: /home/andy/.mozilla/seamonkey/4e39n1np.default/bookmarks.html
Drwxr-xr-x root root /
drwxr-xr-x root root home
drwxrwxr-x andy andy andy
drwxrw-rw- andy andy .mozilla
drwxrw-rw- andy andy seamonkey
drwxrwxrwx andy andy 4e39n1np.default
-rw-r--r-- andy andy bookmarks.html
f: /home/andy/.mozilla/firefox/mltw8z53.default- 1516629000620/bookmarks.html
Drwxr-xr-x root root /
drwxr-xr-x root root home
drwxrwxr-x andy andy andy
drwxrw-rw- andy andy .mozilla
drwxrwxrwx andy andy firefox
drwx------ andy andy mltw8z53.default-1516629000620
-rw-r--r-- andy andy bookmarks.html
@wave5459
andyk_~/Downloads$ rm /home/andy/.mozilla/firefox/mltw8z53.default-1516629000620/bookmarks.html andyk_~/Downloads$
File is deleted. But Firefox recreates it. :-(
And I know you're the owner, but what happens if you try "sudo"? Does bookmarks.html even exist? Are messages maybe piped to /dev/null?
– lightsong Feb 22 '18 at 01:10namei -lx /home/andy/.mozilla/seamonkey/4e39n1np.default/bookmarks.html /home/andy/.mozilla/firefox/mltw8z53.default-1516629000620/bookmarks.html
, please – muru Feb 22 '18 at 02:24rm /home/andy/.mozilla/firefox/mltw8z53.default-1516629000620/bookmarks.html
– lightsong Feb 22 '18 at 03:07