libappindicator-devel is needed as dependency for building xpad in epel8 (ticket #2041567)

libappindicator is part of CentOS 8 / RHEL8 proper, not of EPEL. It looks like libappindicator-devel is unshipped, so you should request it to be added to CRB/PowerTools per https://wiki.centos.org/FAQ/CentOS8/UnshippedPackages

Thank you for the info. I filed a new ticket #2117934 requesting libappindicator-devel for the codeready-builder repo

Please note the copied answer from the corresponding ticket #2117934 from "Tomas Popela" (2022-08-29 11:57:42 UTC):

I know what's going on here and I'm here the one to "blame". First let me mention that:

libappindicator = source package
libappindicator = package built from libappindicator source package providing gtk2 support
libappindicator-python2-appindicator = package built from libappindicator source package providing gtk2 and python2 support
libappindicator-gtk3 = package built from libappindicator source package providing gtk3 support (doesn't depend on libappindicator package)
libappindicator-sharp = package built from libappindicator source package providing Mono support

When RHEL 8 was being developed we were not interested in having libappindicator (and any of its dependencies) in RHEL 8 as we had no use for them in the OS, but Google Chrome required the libappindicator3.so.1 (https://bugs.chromium.org/p/chromium/issues/detail?id=799144):

$ rpm -qpR google-chrome-stable-66.0.3359.181-1.x86_64.rpm | grep app
libappindicator3.so.1()(64bit)

that was provided by the libappindicator-gtk3 package of the libappindicator source package. As we had to disable the python2 support and we were not interested in gtk2 bits and also no Mono stack in RHEL, we've decided to import that libappindicator source package into RHEL 8 and just build and ship libappindicator-gtk3(-devel) from it (in retrospective we should rather introduce it as a libappindicator-gtk3 source package and just don't build it in EPEL) and remove everything else, see https://git.centos.org/rpms/libappindicator/blob/c8/f/SPECS/libappindicator.spec - I made a small mistake that I left the libappindicator-devel subpackage definition there, but as it had no %files section it didn't produce any packages. So my suggestion for getting the libappindicator with gtk2 support into EPEL 8 is to package it there (i.e. using the libappindicator-gtk2 source package name) and build the gtk2 bits from it - there is nothing that we can do about it from RHEL's side.

I saw that you clarified in bug 2117934 comment 1 that you need this to build xpad.  In rawhide, removing the build requirement on libappindicator-devel has no effect on the xpad build.  In fact, it seems that xpad version 5.7 switched from libappindicator to libayatana-appindicator [0], so if you wanted to enable appindicator support in the xpad build (--enable-appindicator) you'd have to build require libayatana-appindicator-devel (which doesn't exist even in rawhide).  I would recommend leaving it off for now and removing that erroneous build requirement to unblock the epel8 build, and closing this bug.

[0] https://bugs.launchpad.net/xpad/+bug/1964116

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