admin: upgrading from Gitea < 1.23 is a two step process

docs/admin/gitea-migration.md

@@ -5,6 +5,11 @@ license: 'CC-BY-SA-4.0'
 
 This guide describes how to go from Gitea to Forgejo if Gitea is installed via a package manager.
 
+Upgrades are supported [up to Gitea v1.22 included](https://forgejo.org/2024-12-gitea-compatibility/), in two steps:
+
+- Upgrade from any Gitea version up to and including v1.22.x to Forgejo v10.0.x
+- Upgrade from Forgejo v10.0.x to any Forgejo version greater than v10.
+
 ## Arch Linux
 
 Arch Linux provides package for both Gitea and Forgejo,

docs/admin/storage.md

@@ -249,10 +249,6 @@ for instance (the plural is not a typo, it is a unification problem) -
 because their behavior is not thoroughly tested and may lead to
 unexpected results.
 
-There are no safeguards preventing the use of undocumented features
-because it may not be backward compatible when upgrading from Gitea to
-Forgejo.
-
 ## Legacy settings
 
 Some settings are deprecated but still supported in the interest of

docs/admin/upgrade.md

@@ -44,6 +44,13 @@ It is **critical** to verify that Forgejo works very carefully. Restoring the ba
 - Manually verify via the web interface. Making a checklist of a typical use case is a good way to not miss anything.
 - If there is a problem of any kind, increase the log level and take a look at the logs. If you cannot figure out what the problem is, ask for help [in the Forgejo chatroom](https://matrix.to/#/#forgejo-chat:matrix.org) before trying to fix it.
 
+## Preparing an upgrade from Gitea
+
+Upgrades to Forgejo are transparently supported [up to Gitea v1.22 included](https://forgejo.org/2024-12-gitea-compatibility/), in two steps:
+
+- Upgrade from any Gitea version up to and including v1.22.x to Forgejo v10.0.x
+- Upgrade from Forgejo v10.0.x to any Forgejo version greater than v10.
+
 ## Preparing the Forgejo upgrade
 
 - Manually analyze (reading the patches to the sources of the template directory) and update the customized CSS / content.