Gmail's Basic HTML mode lacks many of the convenient features of its standard mode, notably bulk operations like mass deletion of messages to free up space. To assist with this, this bookmarklet adds that specific function into the Basic HTML mode.
The tool will select all messages on a Basic HTML Gmail page, then set browser focus on the "Delete" button to speed up the process of mass deletion of filtered emails.
To install the bookmarklet into your Firefox browser, tab until the link labeled "This Bookmarklet" is focused, then press shift+F10, arrow key down to "Bookmark Link...", and press Enter. In the next dialog, provide a name for the bookmark and use the selector labeled "Location" to place the bookmarklet somewhere convenient in your list of bookmarks.
To install the bookmarklet in your Chrome browser, tab until the link labeled "This bookmarklet" is focused, press shift+F10, arrow down to "Copy Link Address...", then press CTRL+Shift+o (The letter Oh) to open Chrome's Bookmark manager. Tab once onto the 3-dot icon labeled "Organize Menu Button SubMenu" and press enter or spacebar to expand that, then arrow down to "Add new bookmark" and press enter or spacebar again. Type in a name for the bookmarklet, then paste you clipboard contents into the URL field.