Updated FAQ

FAQ.md

@@ -4393,10 +4393,12 @@ Deleting messages from the server and restoring them later could result in losin
 
 🌎 [Google Translate](https://translate.google.com/translate?sl=en&u=https://github.com/M66B/FairEmail/blob/master/FAQ.md%23user-content-faq167)
 
+DeepL offers free translation of 500,000 characters (~100,000 words; ~250 pages) every month.
+
 1. Make sure you have the latest version of the app installed
 1. Check if [DeepL](https://www.deepl.com/) supports your language
 1. Enable DeepL support in the miscellaneous settings
-1. [Subscribe to](https://www.deepl.com/pro#developer) the DeepL API Free or Pro plan (credit card required)
+1. [Subscribe to](https://www.deepl.com/pro#developer) the DeepL API Free or Pro plan (credit card required; won't be charged)
 1. [Copy](https://www.deepl.com/pro-account/plan) the authentication key
 1. In the message composer tap on the translate button (文A) in the top action bar, select *Configure* and paste the key