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+RSS-Bridge ships a few options the host may or may not activate. All options are currently defined in the [index.php](https://github.com/RSS-Bridge/rss-bridge/blob/master/index.php) file. This means they'll be reset after upgrading RSS-Bridge!
+
+## Customizable cache timeout
+
+Sometimes it is necessary to specify custom timeouts to update contents more frequent than the bridge maintainer intended. In these cases the client may specify a custom cache timeout to prevent loading contents from cache.
+
+This option can be activated by setting the `CUSTOM_CACHE_TIMEOUT` to `true`. When enabled each bridge receives an additional parameter `Cache timeout in seconds` that can be set to any value between 1 and 86400 (24 hours). If the value is not within the limits the default settings apply (as specified by the bridge maintainer).
+
+The cache timeout is send to RSS-Bridge using the `_cache_timeout` parameter. RSS-Bridge will return an error message if the parameter is received and the option is disabled.
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