Add warning for experimental features (#1314)

Author: katarinasupe

pages/database-management/experimental-features.mdx

@@ -22,6 +22,13 @@ To use experimental features in Memgraph, you first need to [enable
 them](#enabling-experimental-features). In case you experience issues or want to
 provide feedback, please [contact us](#feedback-and-support).
 
+<Callout type="warning">
+If you plan to try out an experimental feature, make sure to start a fresh
+instance and then load your data. Snapshots and WALs created with version
+`vX.Y.Z` without the experimental flag are currently incompatible with the same
+version `vX.Y.Z` when the experimental flag is enabled.
+</Callout>
+
 ## Enabling experimental features
 
 To enable an experimental feature in Memgraph, set `--experimental-enabled` flag

pages/querying/text-search.mdx

@@ -14,6 +14,10 @@ feature](/database-management/experimental-features) introduced in Memgraph
 2.15.1. To use it, start Memgraph with the `--experimental-enabled=text-search`
 flag.
 
+Make sure to start a fresh instance and then load your data. Snapshots and WALs
+created with version `vX.Y.Z` without the experimental flag are currently
+incompatible with the same version `vX.Y.Z` when the experimental flag is
+enabled.
 </Callout>
 
 Text search allows you to look up nodes with properties that contain specific content.