man 1 flatpak-pin

FLATPAK PIN(1)                    flatpak pin                   FLATPAK PIN(1)

NAME
       flatpak-pin - Pin runtimes to prevent automatic removal

SYNOPSIS
       flatpak pin [OPTION...] PATTERN...

DESCRIPTION
       Flatpak maintains a list of patterns that define which refs are pinned.
       A pinned ref will never be automatically uninstalled (as are unused
       runtimes periodically). This can be useful if for example you are using
       a runtime for development purposes.

       Runtimes that are explicitly installed, rather than installed as a
       dependency of something else, are automatically pinned.

       The patterns are just a partial ref, with the * character matching
       anything within that part of the ref. Only runtimes can be pinned, not
       apps. Here are some example patterns:

           org.some.Runtime
           org.some.Runtime//unstable
           runtime/org.domain.*
           org.some.Runtime/arm

       To list the current set of pins, run this command without any patterns.

OPTIONS
       The following options are understood:

       -h, --help
           Show help options and exit.

       --remove
           Instead of adding the patterns, remove matching patterns.

       --user
           Pin refs in a per-user installation.

       --system
           Pin refs in the default system-wide installation.

       --installation=NAME
           Pin refs in a system-wide installation specified by NAME among
           those defined in /etc/flatpak/installations.d/. Using
           --installation=default is equivalent to using --system.

       -v, --verbose
           Print debug information during command processing.

EXAMPLES
       $ flatpak pin

       $ flatpak pin org.freedesktop.Platform//19.08

       $ flatpak pin --remove org.freedesktop.Platform//19.08

SEE ALSO
       flatpak(1), flatpak-uninstall(1),

flatpak                                                         FLATPAK PIN(1)