Update README.fr.md (#3860)

Sync in RSS Guard is now much faster, better (optional) syncing algorithm was implemented

Co-authored-by: Alexandre Alapetite <alexandre@alapetite.fr>
Co-authored-by: maTh <math-home@web.de>

README.fr.md

@@ -228,7 +228,7 @@ et [l’API Fever](https://freshrss.github.io/FreshRSS/fr/users/06_Fever_API.htm
 |:--------------------------------------------------------------------------------------|:-----------:|:-------------------------------------------------------------:|:----------------------:|:----------------:|:-------------:|:---------:|:------------------------------:|:-------------------:|:----------:|:------:|:--------:|:------------:|
 | [News+](https://github.com/noinnion/newsplus/blob/master/apk/NewsPlus_202.apk) with [Google Reader extension](https://github.com/noinnion/newsplus/blob/master/apk/GoogleReaderCloneExtension_101.apk) | Android | [Partially](https://github.com/noinnion/newsplus/blob/master/extensions/GoogleReaderCloneExtension/src/com/noinnion/android/newsplus/extension/google_reader/) | 2015       | GReader | ✔️             | ⭐⭐⭐       | ✔️                    | ✔️                 | ✔️         | ✔️     | ✔️       | ✔️           |
 | [FeedMe](https://play.google.com/store/apps/details?id=com.seazon.feedme)             | Android     | ➖                                                            | ✔️✔️                   | GReader          | ✔️            | ⭐⭐        | ➖                             | ➖                  | ✔️         | ✓     | ✔️       | ✔️           |
-| [RSS Guard](https://github.com/martinrotter/rssguard) | Windows, GNU/Linux, macOS, OS/2 | ✔️ | ✔️✔️ | GReader | ✔️ | ⭐ | ➖ | ✔️ | ✔️ | ✔️ | ✔️ | ➖ |
+| [RSS Guard](https://github.com/martinrotter/rssguard) | Windows, GNU/Linux, macOS, OS/2 | ✔️ | ✔️✔️ | GReader | ✔️ | ⭐⭐ | ➖ | ✔️ | ✔️ | ✔️ | ✔️ | ➖ |
 | [EasyRSS](https://github.com/Alkarex/EasyRSS)                                         | Android     | [✔️](https://github.com/Alkarex/EasyRSS)                      | ✔️                     | GReader          | Bug           | ⭐⭐        | ➖                             | ➖                  | ✔️         | ➖     | ➖       | ➖           |
 | [FocusReader](https://play.google.com/store/apps/details?id=allen.town.focus.reader)  | Android     | ➖                                                            | ✔️✔️                   | GReader          | ✔️            | ⭐⭐⭐       | ➖                             | ➖                  | ✔️         | ➖     | ✓      | ✔️           |
 | [Readrops](https://github.com/readrops/Readrops)                                      | Android     | [✔️](https://github.com/readrops/Readrops)                    | ✔️✔️                   | GReader          | ✔️            | ⭐⭐⭐       | ➖                             | ➖                  | ➖         | ➖     | ➖       | ✔️           |