on_install/on_enable fire only on a state transition, so a permission declared by a later plugin version never reached an already-installed site through them. Until someone ran flask seed permissions by hand the name did not exist, and any route guarding on it refused every caller. Settings already had sync_all_plugin_settings() on the upgrade path for exactly this reason; permissions now have the counterpart.
The scope relink is the half that actually bites. Creating the Permission row only makes the name exist - the prebuilt scopes derive their grants from the catalog, so a permission seeded without a following Role.seedscopes() belongs to nobody but admin. The plugin installs clean and its UI is invisible to every non-admin, which reads as a broken plugin rather than a seeding gap. Ordering matches flask seed permissions: seedscopes only links rows that already exist, so it runs last. Additive, so a site's deliberate role edits survive the deploy, and best-effort per plugin so one bad plugin cannot abort a deploy.
Test deletes an existing plugin permission, runs upgrade-all, and asserts both that the row returns and that it is granted to the technician scope. Verified it fails without the fix rather than passing vacuously.
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