all: Transition to using fs watcher by default (fixes #4552)

lib/config/config.go

@@ -32,7 +32,7 @@ import (
 
 const (
 	OldestHandledVersion = 10
-	CurrentVersion       = 27
+	CurrentVersion       = 28
 	MaxRescanIntervalS   = 365 * 24 * 60 * 60
 )
 
@@ -315,6 +315,9 @@ func (cfg *Configuration) clean() error {
 	if cfg.Version == 26 {
 		convertV26V27(cfg)
 	}
+	if cfg.Version == 27 {
+		convertV27V28(cfg)
+	}
 
 	// Build a list of available devices
 	existingDevices := make(map[protocol.DeviceID]bool)
@@ -374,6 +377,12 @@ func (cfg *Configuration) clean() error {
 	return nil
 }
 
+func convertV27V28(cfg *Configuration) {
+	// Show a notification about enabling filesystem watching
+	cfg.Options.UnackedNotificationIDs = append(cfg.Options.UnackedNotificationIDs, "fsWatcherNotification")
+	cfg.Version = 28
+}
+
 func convertV26V27(cfg *Configuration) {
 	for i := range cfg.Folders {
 		f := &cfg.Folders[i]