URL: https://viewer-ebook.books.com.tw/viewer/epub/?book_uni_id=0010763244_reflowable_trial

Browser / Version: Firefox 90.0 (64-bit)
Operating System: Linux x86_64
Tested Another Browser: Yes Other

Problem type: Site is not usable
Description: Browser unsupported
Steps to Reproduce:
I tried to read a free sample of a book on "博客來", a platform selling books. First, I went to this page https://www.books.com.tw/products/0010763244 . I clicked the orange "試閱" (read free sample) button under the big thumbnail of the book. Another tab popped up and said that they only support Chrome and Safari. I changed my user agent from Firefox to Chrome, and the site magically worked.

View the screenshot

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