[1] Make your site shine in Speed Dial - Dev.Opera ( 版) https://rawgit.com/operasoftware/devopera-static-backup/master/http/dev.opera.com/articles/view/opera-speed-dial-enhancements/index.html#preview-refresh

To make Speed Dial content more dynamic, you can define an autoreloading behavior that will be used if the user adds the site to a Speed Dial slot. You can set this in two ways:

Using a meta tag:

<meta http-equiv="preview-refresh" content="3600">

Setting Preview-Refresh as a response header:

Preview-Refresh:3600

Note that the value is set in seconds. 3600 will thus reload the Speed Dial entry every hour.