Instead of specifying only one font for each style, it would be useful to be able to insert a (comma separated) list of fonts, which would then used according to the available fonts on each machine. The same way the CSS font-family Property (http://www.w3schools.com/cssref/pr_font_font-family.asp)works. This would be very useful to exchange documents with other people who might not have your fonts, or to work with the same document on different computers, without loosing entirely the intended appearance of the document.
Bad idea. Text documents are created to keep some kind of layout, which is not attainable with multiple possible fonts.
(In reply to comment #1) > Bad idea. Text documents are created to keep some kind of layout, which is > not attainable with multiple possible fonts. But to assure a desired layout (regardless of the available fonts in each machine) is the main idea of specifying a list of fonts. For instance, I often use Helvetica, but most computers do not have Helvetica installed by default. If I could specify "Helvetica, Arial" in the paragraph style, this would guarantee that if the user doesn't have Helvetica, he would see the document with Arial, which is similar and keeps a "kind of layout" like you mentioned.
Adding needsUXeval as I don't see how this can be implemented in the UI and if this is a good idea anyway, see comment 1.
Rather than putting too much effort in a weird configuration we should guarantee that documents are shown properly when the font is not installed. That means Helvetica is replaced by Arial, which is the fact, and <Foo> by <Bar>, which needs some coding. The proposal is here https://design.blog.documentfoundation.org/2016/10/21/dealing-with-missing-fonts/ with an addition at https://design.blog.documentfoundation.org/2018/02/18/improvements-font-listing/ I would close this ticket as WF, also since we are bound to the file format. And not having checked the specs I guess it defines a font name and not a list of fonts.