Created attachment 1430572[details]
single_and_list_display.gif
Fixed! Custom button is appearing on datastore object type with 'Single' as well as 'List' view display for option.
Found new issue related to dialog submission, raised at BZ1558544.
Verifying this since found issue does not affect behavior of appearance.
Verified on - 5.9.2.4.20180501195858_35dc609
Thx!
Since the problem described in this bug report should be
resolved in a recent advisory, it has been closed with a
resolution of ERRATA.
For information on the advisory, and where to find the updated
files, follow the link below.
If the solution does not work for you, open a new bug report.
https://access.redhat.com/errata/RHSA-2018:1328