Firefox on Debian Linux reports using the font “Helvetica‭‬עבה”; how to find the file for this font?

[AlMa1r]

While inspecting a particular Web site in Firefox on Debian, I saw that a font “Helvetica‭‬עבה” is reported. How do I find the locally installed file, from which this font was taken? I simply have too many (437) Helvetica-like fonts in /usr/local/share/fonts, so I'm unable to examine them one by one. Hovering with a mouse over the font name yields me text in a font looking like Helvetica bold. Recursively grepping for "Helvetica‭‬עבה" in /usr, /var, and /etc yields no results, and,  to the best of my knowledge, I have no fonts in my user directory (except in local TeX Live installations) that could be used by Firefox.