Sitecore Preview Performance and WebEditRibbon

version 6.5.0 update 3

Using HttpWatch our developer could see that when opening the preview window, the WebEditRibbon was taking a long time to load, the following url was taking around seven seconds to load:

http://[my domain]/sitecore/shell/Applications/WebEdit/WebEditRibbon.aspx?db=master&id=%7b77B0581A-4F5F-43EB-B9C1-DDA135319B18%7d&la=da&vs=49&url=%2f%3fsc_itemid%3d%257d87C0581A-4F5F-43EB-B9C1-DDA135319B18%257d%26sc_mode%3dpreview%26sc_lang%3dda&mode=preview&sc_pagesite=website&trf=%2ftemp%2fdiagnostics%2ftrace_%7b8cdbebc7-1ad4-4f36-9f04-74bf665f2c63%7d.xml&prf=%2ftemp%2fdiagnostics%2fprofile_%7b8cdbebc7-1ad4-4f36-9f04-74bf665f2c63%7d.xml&dev=%7bFE5E7FEF-89C0-4D99-9AA3-B5FBD009C9F3%7d

After a quick search I found Alex Shyba had experienced a similar performance issues with the Page Editor which was caused by a feature of the Page Editor menu which counted the number of items an editor has checked out. The fix was to add the following Sitecore setting to the websites web.config

<setting name="WebEdit.ShowNumberOfLockedItemsOnButton" value="false" />

Our customer's Sitecore master database was several Gbytes and once we added this to our web.config all our preview problem disappeared and we had happy editors again :o)