Transifex seems to have kept a record of it, since it shows up in the suggestions box, but we do not have a way to tell Transifex to apply all strings that have a 100% match to their suggestion.
It might be possible to use "msgmerge" to merge the older and newer file (or maybe poedit has a feature for that, but I'm not sure), then to re-upload the meged file to Transifex. Only one component is affected ("mailing", common-components only had ~ 6 strings affected).
The 10% drop on Transifex is because I also uploaded the 4.7 strings. Looking at untranslated strings in French, it has ~ 158 untranslated strings (it was at 100%, if I recall correctly). Using another metric , it gives me about 140-150 strings that had been lost.
 git show 84234c17272c8e7f0d08b9652af81cd0604aa18b po/pot/mailing.pot | grep msgid | grep ^+ | wc -l