Re: General question about installing applications etc from repos
As far as I know, the packman repos are managed, at least in part, by some of the volunteers to maintain opensuse packages. So you usually won't run into problems keeping the packman repo around.
If you use "zypper dup" to go to the next version (maybe 42.2), then remove or disable packman first. If you are staying at 42.1, then you probably should be using "zypper up" and not "zypper dup".
Apart from that, add repos with care. After adding a repo for a specific install, you can disable that repo. That way it stays around but isn't used.
For Leap 42.1, I currently have the opensuse repos that were set at install. I also have the Packman and libdvdcss repos available from the community repos list. On one machine with Nvidia graphics, I will add the Nvidia repo when it shows up in the community repos list. I don't plan an adding any others.
openSUSE Leap 15.2; KDE Plasma 5.18.5;
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