diff --git a/Compatibility-issues.md b/Compatibility-issues.md
index 1fa6125..4c73fe3 100644
--- a/Compatibility-issues.md
+++ b/Compatibility-issues.md
@@ -118,4 +118,16 @@ You don't even need to close Arduino, just re-open the library manager.
 
 Due to the non-standard library structure, ArduinoJson won't compile for older versions of Visual Micro - the solution is simply to upgrade to Visual Micro from January 2016 or later.
 
-See issue [#238](https://github.com/bblanchon/ArduinoJson/issues/238).
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+See issue [#238](https://github.com/bblanchon/ArduinoJson/issues/238).
+
+## WifiManager
+
+There is a [known bug](https://github.com/tzapu/WiFiManager/commit/44e828e77a2454a38371f7d5fb64424acebeb676) in the WifiManager library < 0.12.
+
+This caused a compilation error in ArduinoJson:
+
+    ArduinoJson/include/ArduinoJson/Internals/../Internals/../Polyfills/isNaN.hpp:29:17: error: 'isnan' was not declared in this scope
+
+To fix the issue, simply upgrade WifiManager to >= 0.12
+
+See issue [#284](https://github.com/bblanchon/ArduinoJson/issues/284)
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