Add a configuration key to disable driveless mode

www/common/application_config_internal.js

@@ -190,5 +190,13 @@ define(function() {
     // but this number depends on the network and CPU performances of each user's device.
     config.degradedLimit = 8;
 
+    // In "legacy" mode, one-time users were always creating an "anonymous" drive when visiting CryptPad
+    // in which they could store their pads. The new "driveless" mode allow users to open an existing
+    // pad without creating a drive in the background. The drive will only be created if they visit
+    // a different page (Drive, Settings, etc.) or try to create a new pad themselves. You can disable
+    // the driveless mode by changing the following value to "false"
+    config.allowDrivelessMode = true;
+    config.allowDrivelessMode = true;
+
     return config;
 });

www/common/sframe-common-outer.js

@@ -222,7 +222,7 @@ define([
                 } catch (e) { console.error(e); }
 
                 Cryptpad.ready(waitFor(), {
-                    noDrive: cfg.noDrive,
+                    noDrive: cfg.noDrive && AppConfig.allowDrivelessMode,
                     driveEvents: cfg.driveEvents,
                     cache: Boolean(cfg.cache),
                     currentPad: currentPad