Merge pull request #9808 from doing-art/off/770-documentation-for-persistent-opfs

Documented how to enhance persistent mode in the browser file storage (OPFS)

Author: ConnorLand

content/en/docs/refguide/mobile/building-efficient-mobile-apps/offlinefirst-data/best-practices.md

@@ -139,3 +139,16 @@ Datagrids can not have columns with attributes from related entities in offline
 ### Attribute Paths in Sort Orders
 
 Attribute paths can not be used in sort orderings in offline apps.
+
+## Enhancing Persistent Mode in File Storage {#persistent-mode}
+
+When using offline profiles, files are stored locally on a user's device in the browser Origin Private File System (OPFS). The OPFS can operate in two modes: **persistent** and **best-effort**. The **persistent** mode is preferable because it offers greater storage capacity and better data durability. While **persistent** mode is used by default, a browser may opt for **best-effort** mode if it assesses the site's importance as low. This assessment is made based on internal browser heuristics, which include the following:
+* The level of site engagement
+* Whether the site has been bookmarked
+* Whether permission for site notifications has been granted
+
+To enhance the likelihood of operating the OPFS in 'persistent' mode, consider taking the following actions:
+* Bookmark the site
+* Enable notifications for the site
+
+Firefox does not utilize heuristics but instead displays a popup requesting permission to use **persistent** mode. To proceed, simply click **Allow** in the popup.