diff --git a/lib/config/optionsconfiguration.go b/lib/config/optionsconfiguration.go
index 3f8478917..a0a147705 100644
--- a/lib/config/optionsconfiguration.go
+++ b/lib/config/optionsconfiguration.go
@@ -74,16 +74,13 @@ type OptionsConfiguration struct {
 	// The maximum number of connections which we will allow in total, zero
 	// meaning no limit. Affects incoming connections and prevents
 	// attempting outgoing connections.
-	ConnectionLimitMax int `json:"connectionLimitMax" xml:"connectionLimitMax"`
-	// When set, this allows TLS 1.2 on sync connections, where we otherwise
-	// default to TLS 1.3+ only.
-	InsecureAllowOldTLSVersions        bool `json:"insecureAllowOldTLSVersions" xml:"insecureAllowOldTLSVersions"`
-	ConnectionPriorityTCPLAN           int  `json:"connectionPriorityTcpLan" xml:"connectionPriorityTcpLan" default:"10"`
-	ConnectionPriorityQUICLAN          int  `json:"connectionPriorityQuicLan" xml:"connectionPriorityQuicLan" default:"20"`
-	ConnectionPriorityTCPWAN           int  `json:"connectionPriorityTcpWan" xml:"connectionPriorityTcpWan" default:"30"`
-	ConnectionPriorityQUICWAN          int  `json:"connectionPriorityQuicWan" xml:"connectionPriorityQuicWan" default:"40"`
-	ConnectionPriorityRelay            int  `json:"connectionPriorityRelay" xml:"connectionPriorityRelay" default:"50"`
-	ConnectionPriorityUpgradeThreshold int  `json:"connectionPriorityUpgradeThreshold" xml:"connectionPriorityUpgradeThreshold" default:"0"`
+	ConnectionLimitMax                 int `json:"connectionLimitMax" xml:"connectionLimitMax"`
+	ConnectionPriorityTCPLAN           int `json:"connectionPriorityTcpLan" xml:"connectionPriorityTcpLan" default:"10"`
+	ConnectionPriorityQUICLAN          int `json:"connectionPriorityQuicLan" xml:"connectionPriorityQuicLan" default:"20"`
+	ConnectionPriorityTCPWAN           int `json:"connectionPriorityTcpWan" xml:"connectionPriorityTcpWan" default:"30"`
+	ConnectionPriorityQUICWAN          int `json:"connectionPriorityQuicWan" xml:"connectionPriorityQuicWan" default:"40"`
+	ConnectionPriorityRelay            int `json:"connectionPriorityRelay" xml:"connectionPriorityRelay" default:"50"`
+	ConnectionPriorityUpgradeThreshold int `json:"connectionPriorityUpgradeThreshold" xml:"connectionPriorityUpgradeThreshold" default:"0"`
 	// Legacy deprecated
 	DeprecatedUPnPEnabled        bool     `json:"-" xml:"upnpEnabled,omitempty"`        // Deprecated: Do not use.
 	DeprecatedUPnPLeaseM         int      `json:"-" xml:"upnpLeaseMinutes,omitempty"`   // Deprecated: Do not use.
diff --git a/lib/syncthing/syncthing.go b/lib/syncthing/syncthing.go
index cf1397f1e..e43a04d25 100644
--- a/lib/syncthing/syncthing.go
+++ b/lib/syncthing/syncthing.go
@@ -252,13 +252,7 @@ func (a *App) startup() error {
 	// The TLS configuration is used for both the listening socket and outgoing
 	// connections.
 
-	var tlsCfg *tls.Config
-	if a.cfg.Options().InsecureAllowOldTLSVersions {
-		l.Infoln("TLS 1.2 is allowed on sync connections. This is less than optimally secure.")
-		tlsCfg = tlsutil.SecureDefaultWithTLS12()
-	} else {
-		tlsCfg = tlsutil.SecureDefaultTLS13()
-	}
+	tlsCfg := tlsutil.SecureDefaultTLS13()
 	tlsCfg.Certificates = []tls.Certificate{a.cert}
 	tlsCfg.NextProtos = []string{bepProtocolName}
 	tlsCfg.ClientAuth = tls.RequestClientCert