I've just released a first version of a Chrome Extension for enhanced support of Qt Developer Network.
It adds a Qt API documentation search shortcut to Chrome's omnibox: Just type qdoc + space or tab + the start of the class you're interested in. A list of matching class names is loaded automatically and presented as a list.
On all pages with search results on the forums (e.g. "Posts since last visit":/forums/new_topic_search, unanswered posts, active topics, results of general searches), you get a "Mark as read" box, on hovering over a certain thread topic. Just click on the button to make that thread read, so that it doesn't shop up in the search results anymore. This functionality is only available for the mentioned search results at the moment, but not on the regular forum listings.
On the options page (screw icon / tools / extensions) of this extension you can choose whether a topic which is "read" with the button is greyed out or entirely hidden and which Qt version should be used for the display of the API docs. Defaults are to grey out and use the site default of Qt Project.
Get the extension at the "Google Chrome Webstore":https://chrome.google.com/webstore/detail/mpoinnifdaalghpconbihmjcgpabkjoe
Big thanks to "peppe":/member/5319, whose code for a greasemonkey script for a "Per-thread “Mark as read” button":/forums/viewthread/12303/ is the base for the same functionality of this extension!
EDIT: Updated the description, thanks koahnig.