Question Author
Thanks Hans, holding down Control then + solved the problem. Thanks biblebub for the photo of how yours appears. It is exactly how my partners is (or was until trying Hans suggestion). The strange thing is that my partners has only just started to appear small, so no idea why. She used Chrome browser, I use Firefox.
It looks like she'll just need to go through the process each time she views BBC News as most others sites appear ok.
Thanks again to you both