diff --git a/lib/lib_div/OpenTherm-0.9.0/tasmota_lib_changes.md b/lib/lib_div/OpenTherm-0.9.0/tasmota_lib_changes.md
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+Attention when updating library. Changes in lib needed!!
+All OpenTherm constants shall be prepended with `OPTH_` to avoid conflicts with other libs.
+
+See commit https://github.com/arendst/Tasmota/commit/960291729ccc7cb4da50108e5299d44a79cb06de
+
+As of OpenTherm-0.9.0, hte list is:
+        OPTH_NONE
+        OPTH_SUCCESS
+        OPTH_INVALID
+        OPTH_TIMEOUT
+        OPTH_READ_DATA
+        OPTH_READ
+        OPTH_WRITE_DATA
+        OPTH_WRITE
+        OPTH_INVALID_DATA
+        OPTH_RESERVED
+        OPTH_READ_ACK
+        OPTH_WRITE_ACK
+        OPTH_DATA_INVALID
+        OPTH_UNKNOWN_DATA_ID
+        OPTH_NOT_INITIALIZED
+        OPTH_READY
+        OPTH_DELAY
+        OPTH_REQUEST_SENDING
+        OPTH_RESPONSE_WAITING
+        OPTH_RESPONSE_START_BIT
+        OPTH_RESPONSE_RECEIVING
+        OPTH_RESPONSE_READY
+        OPTH_RESPONSE_INVALID