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Login to VIA
Go to Website > Pages (if the window title or meta description you want to edit is for a blog article, go to Website > Blog instead)
Use the search bar to search for the page or blog you want to edit
Double click the relevant page from the list, or right click and select edit
A new tab will open showing a wireframe layout of the page. Click the top underlined section which is the name of the page
A window will fly out from the right. Scroll to the section entitled Window Title or Meta Description (depending on what part you want to edit) and enter the relevant text you want to add
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