In British English the plural form DVDs is considered correct whereas in American English it is considered to be incorrect. No suitable alternative is presented.Same for CD and probably more.
One cat, two cats. One CD, two CDs. One DVD, two DVDs.
Please supply a reference.
Chicago Manual of Style, 15th edition, section 7.15 says that for capital letters used as words, the plural is usually formed by adding an 's' (no apostrophe). It gives these uppercase examples: the three Rs; IRAs; URLs.
In case this was not clear from my initial post: I subscribed to this forum because I am using language tools and because language tools is doing something which surprises me.
Language tools is telling me "DVDs" is incorrect, when the language is American English.
To see this for yourself: https://languagetool.org/ and fill in "DVDs". Select English and American, Check Text (sic).
Thanks for the report. LanguageTool is not correct. I added the problem to my task list.
@alexb, fixed (https://github.com/languagetool-org/languagetool/commit/c9e90b5c3ebf2e5175ed15e40179aacc179d013d).
The change will become active tomorrow.