Comment # 3 on bug 969159 from Andreas Stieger

zypper in subversion=1.8.15
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Reading installed packages...
There is an update candidate 'subversion-1.9.3-223.1.x86_64' for
'subversion-1.8.10-6.1.x86_64', but it does not match the specified version,
architecture, or repository.
There is an update candidate for 'subversion', but it is from a different
vendor. Use 'zypper install subversion-1.9.3-223.1.x86_64' to install this
candidate.
Resolving package dependencies...

Problem: subversion-1.8.15-2.1.x86_64 conflicts with libsvn_auth_kwallet-1-0 <
1.8.15 provided by libsvn_auth_kwallet-1-0-1.8.10-6.1.x86_64
 Solution 1: Following actions will be done:
  install libsvn_auth_kwallet-1-0-1.8.15-2.1.x86_64 (with vendor change)
    openSUSE  -->  obs://build.opensuse.org/devel:tools
  install subversion-bash-completion-1.8.15-2.1.noarch (with vendor change)
    openSUSE  -->  obs://build.opensuse.org/devel:tools
 Solution 2: do not install subversion-1.8.15-2.1.x86_64

Choose from above solutions by number or cancel [1/2/c] (c): 1
Resolving dependencies...
Resolving package dependencies...

The following 3 packages are going to be upgraded:
  libsvn_auth_kwallet-1-0 subversion subversion-bash-completion

The following 3 packages are going to change vendor:
  libsvn_auth_kwallet-1-0     openSUSE -> obs://build.opensuse.org/devel:tools
  subversion                  openSUSE -> obs://build.opensuse.org/devel:tools
  subversion-bash-completion  openSUSE -> obs://build.opensuse.org/devel:tools


3 packages to upgrade, 3  to change vendor.
Overall download size: 2.3 MiB. Already cached: 0 B. After the operation,
additional 12.7 KiB will be use


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On SLE 12 / Leap 42.1, adding the Requires: %{name} = %{version} to the plugins
should address this (possibly also the supplements)