优化

app/src/main/java/io/legado/app/help/storage/Restore.kt

@@ -220,12 +220,17 @@ object Restore {
                 if (BackupConfig.keyIsNotIgnore(key)) {
                     when (key) {
                         PreferKey.webDavPassword -> {
-                            edit.putString(
-                                key,
-                                kotlin.runCatching {
-                                    aes.decryptStr(value.toString())
-                                }.getOrDefault(value.toString())
-                            )
+                            kotlin.runCatching {
+                                aes.decryptStr(value.toString())
+                            }.getOrNull()?.let {
+                                edit.putString(key, it)
+                            } ?: let {
+                                if (appCtx.getPrefString(PreferKey.webDavPassword)
+                                        .isNullOrBlank()
+                                ) {
+                                    edit.putString(key, value.toString())
+                                }
+                            }
                         }
 
                         else -> when (value) {