Allow left-hand menu to be hidden in text only mode to support enlarging text
When using text-only mode the text of the book can be enlarged using browser zoom to a higher level than when text-only mode is disabled (when using Read Online or download views). For visually impaired users who need to enlarge text to a higher level of magnification than non text-only Read Online or downloads will allow, text-only mode should meet this need. However, as the text is enlarged using browser zoom the left-hand menu (containing table of contents, search etc) also increases in size, covering the book content. The left-hand menu cannot be closed (as it can when text-only mode is disabled). At a zoom level of only 175% the book becomes unusable. If the left-hand menu could be closed and reopened when needed this would solve the problem.
Sarah George commented
Excellent idea, this is vital to our users
I'm not sure why the menu can't be closed when in text-only mode, it makes the text completely inaccessible. The only way round this issue seems to be to change the settings to disable text-only mode, close the side menu, then change the settings back to text only mode, which is very clunky.