diff --git a/ChangeLog.adoc b/ChangeLog.adoc
index 836b37328..6649a1bad 100644
--- a/ChangeLog.adoc
+++ b/ChangeLog.adoc
@@ -22,6 +22,10 @@ New features::
 
   * api: add info "uptime_current"
 
+Bug fixes::
+
+  * irc: fix duplicated channels in autojoin option when autojoin_dynamic is enabled (issue #1795)
+
 [[v3.6]]
 == Version 3.6 (2022-07-10)
 
diff --git a/src/plugins/irc/irc-join.c b/src/plugins/irc/irc-join.c
index 4a4a024ea..af388d03c 100644
--- a/src/plugins/irc/irc-join.c
+++ b/src/plugins/irc/irc-join.c
@@ -32,6 +32,32 @@
 #include "irc-server.h"
 
 
+/*
+ * Compares two join channels: name and key.
+ */
+
+int
+irc_join_compare_join_channel (struct t_irc_server *server,
+                               struct t_irc_join_channel *join_channel1,
+                               struct t_irc_join_channel *join_channel2)
+{
+    int rc;
+
+    rc = irc_server_strcasecmp (server,
+                                join_channel1->name, join_channel2->name);
+    if (rc != 0)
+        return rc;
+
+    if (!join_channel1->key && !join_channel2->key)
+        return 0;
+    if (join_channel1->key && !join_channel2->key)
+        return -1;
+    if (!join_channel1->key && join_channel2->key)
+        return 1;
+
+    return strcmp (join_channel1->key, join_channel2->key);
+}
+
 /*
  * Compares two join channels (no sort, keyed channels first).
  */
@@ -112,6 +138,21 @@ irc_join_compare_sort_cb (void *data, struct t_arraylist *arraylist,
  * Frees a join channel.
  */
 
+void
+irc_join_free_join_channel (struct t_irc_join_channel *join_channel)
+{
+    if (join_channel->name)
+        free (join_channel->name);
+    if (join_channel->key)
+        free (join_channel->key);
+
+    free (join_channel);
+}
+
+/*
+ * Callback called to free a join channel.
+ */
+
 void
 irc_join_free_cb (void *data, struct t_arraylist *arraylist, void *pointer)
 {
@@ -122,34 +163,74 @@ irc_join_free_cb (void *data, struct t_arraylist *arraylist, void *pointer)
     (void) arraylist;
 
     ptr_join_chan = (struct t_irc_join_channel *)pointer;
-
-    if (ptr_join_chan->name)
-        free (ptr_join_chan->name);
-    if (ptr_join_chan->key)
-        free (ptr_join_chan->key);
-    free (ptr_join_chan);
+    irc_join_free_join_channel (ptr_join_chan);
 }
 
 /*
  * Removes all occurrences of a channel from the array list then adds the
  * join channel (channel + key).
+ *
+ * Returns:
+ *   1: join channel added to the list
+ *   0: join channel NOT added to the list
+ *      (the caller must then free it if needed)
  */
 
-void
+int
 irc_join_arraylist_add (struct t_arraylist *arraylist,
-                        void *pointer)
+                        struct t_irc_server *server,
+                        struct t_irc_join_channel *join_channel)
 {
-    int index;
+    struct t_irc_join_channel *ptr_join_chan, *ptr_join_chan_exact;
+    int index, removed;
 
-    while (1)
+    index = 0;
+    ptr_join_chan_exact = NULL;
+    while (index < weechat_arraylist_size (arraylist))
     {
-        weechat_arraylist_search (arraylist, pointer, &index, NULL);
-        if (index < 0)
-            break;
-        weechat_arraylist_remove (arraylist, index);
+        ptr_join_chan = weechat_arraylist_get (arraylist, index);
+        removed = 0;
+        if (ptr_join_chan)
+        {
+            if (irc_join_compare_join_channel (server,
+                                               ptr_join_chan,
+                                               join_channel) == 0)
+            {
+                if (ptr_join_chan_exact)
+                {
+                    weechat_arraylist_remove (arraylist, index);
+                    removed = 1;
+                }
+                else
+                {
+                    ptr_join_chan_exact = ptr_join_chan;
+                }
+            }
+            else if (irc_server_strcasecmp (server, ptr_join_chan->name,
+                                            join_channel->name) == 0)
+            {
+                weechat_arraylist_remove (arraylist, index);
+                removed = 1;
+            }
+        }
+        if (!removed)
+            index++;
     }
 
-    weechat_arraylist_add (arraylist, pointer);
+    if (ptr_join_chan_exact)
+    {
+        free (ptr_join_chan_exact->name);
+        ptr_join_chan_exact->name = strdup (join_channel->name);
+        if (ptr_join_chan_exact->key)
+            free (ptr_join_chan_exact->key);
+        ptr_join_chan_exact->key = (join_channel->key) ?
+            strdup (join_channel->key) : NULL;
+        return 0;
+    }
+
+    weechat_arraylist_add (arraylist, join_channel);
+
+    return 1;
 }
 
 /*
@@ -225,7 +306,8 @@ irc_join_split (struct t_irc_server *server, const char *join, int sort)
         new_channel = (struct t_irc_join_channel *)malloc (sizeof (*new_channel));
         new_channel->name = strdup (channels[i]);
         new_channel->key = (i < count_keys) ? strdup (keys[i]) : NULL;
-        irc_join_arraylist_add (arraylist, new_channel);
+        if (!irc_join_arraylist_add (arraylist, server, new_channel))
+            irc_join_free_join_channel (new_channel);
     }
 
 end:
@@ -333,7 +415,8 @@ irc_join_add_channel (struct t_irc_server *server,
     join_chan = (struct t_irc_join_channel *)malloc (sizeof (*join_chan));
     join_chan->name = strdup (channel_name);
     join_chan->key = (key && key[0]) ? strdup (key) : NULL;
-    irc_join_arraylist_add (arraylist, join_chan);
+    if (!irc_join_arraylist_add (arraylist, server, join_chan))
+        irc_join_free_join_channel (join_chan);
 
     new_join = irc_join_build_string (arraylist);
 
@@ -384,7 +467,8 @@ irc_join_add_channels (struct t_irc_server *server,
         join_chan->name = strdup (ptr_join_chan->name);
         join_chan->key = (ptr_join_chan->key && ptr_join_chan->key[0]) ?
             strdup (ptr_join_chan->key) : NULL;
-        irc_join_arraylist_add (arraylist, join_chan);
+        if (!irc_join_arraylist_add (arraylist, server, join_chan))
+            irc_join_free_join_channel (join_chan);
     }
 
     new_join = irc_join_build_string (arraylist);
@@ -547,7 +631,8 @@ irc_join_save_channels_to_autojoin (struct t_irc_server *server)
             join_chan->name = strdup (ptr_channel->name);
             join_chan->key = (ptr_channel->key && ptr_channel->key[0]) ?
                 strdup (ptr_channel->key) : NULL;
-            irc_join_arraylist_add (arraylist, join_chan);
+            if (!irc_join_arraylist_add (arraylist, server, join_chan))
+                irc_join_free_join_channel (join_chan);
         }
     }
 
diff --git a/tests/unit/plugins/irc/test-irc-join.cpp b/tests/unit/plugins/irc/test-irc-join.cpp
index de40dd24b..54b8076b0 100644
--- a/tests/unit/plugins/irc/test-irc-join.cpp
+++ b/tests/unit/plugins/irc/test-irc-join.cpp
@@ -32,6 +32,11 @@ extern "C"
 #include "src/plugins/irc/irc-channel.h"
 #include "src/plugins/irc/irc-join.h"
 #include "src/plugins/irc/irc-server.h"
+
+extern int irc_join_compare_join_channel (struct t_irc_server *server,
+                                          struct t_irc_join_channel *join_channel1,
+                                          struct t_irc_join_channel *join_channel2);
+
 }
 
 #define WEE_CHECK_ADD_CHANNEL(__result, __join, __channel, __key)       \
@@ -90,9 +95,52 @@ TEST_GROUP(IrcJoin)
 {
 };
 
+/*
+ * Tests functions:
+ *   irc_join_compare_join_channel
+ */
+
+TEST(IrcJoin, CompateJoinChannel)
+{
+    struct t_irc_join_channel join_chan1, join_chan2;
+
+    join_chan1.name = NULL;
+    join_chan1.key = NULL;
+    join_chan2.name = NULL;
+    join_chan2.key = NULL;
+
+    LONGS_EQUAL(0, irc_join_compare_join_channel (NULL, &join_chan1, &join_chan2));
+
+    join_chan1.name = strdup ("#abc");
+    LONGS_EQUAL(1, irc_join_compare_join_channel (NULL, &join_chan1, &join_chan2));
+
+    join_chan2.name = strdup ("#abc");
+    LONGS_EQUAL(0, irc_join_compare_join_channel (NULL, &join_chan1, &join_chan2));
+
+    join_chan1.key = strdup ("key_abc");
+    LONGS_EQUAL(-1, irc_join_compare_join_channel (NULL, &join_chan1, &join_chan2));
+
+    join_chan2.key = strdup ("key_abc");
+    LONGS_EQUAL(0, irc_join_compare_join_channel (NULL, &join_chan1, &join_chan2));
+
+    free (join_chan2.key);
+    join_chan2.key = strdup ("key2_abc");
+    LONGS_EQUAL(45, irc_join_compare_join_channel (NULL, &join_chan1, &join_chan2));
+
+    free (join_chan2.name);
+    join_chan2.name = strdup ("#def");
+    LONGS_EQUAL(-1, irc_join_compare_join_channel (NULL, &join_chan1, &join_chan2));
+
+    free (join_chan1.name);
+    free (join_chan1.key);
+    free (join_chan2.name);
+    free (join_chan2.key);
+}
+
 /*
  * Tests functions:
  *   irc_join_compare_cb
+ *   irc_join_free_join_channel
  *   irc_join_free_cb
  *   irc_join_split
  *   irc_join_build_string
@@ -211,6 +259,22 @@ TEST(IrcJoin, SplitBuildString)
     free (autojoin);
     arraylist_free (arraylist);
 
+    /* duplicated channel */
+    arraylist = irc_join_split (NULL, "#abc,#def,#abc", 0);
+    CHECK(arraylist);
+    LONGS_EQUAL(2, arraylist->size);
+    channels = (struct t_irc_join_channel **)arraylist->data;
+    CHECK(channels[0]);
+    STRCMP_EQUAL("#abc", channels[0]->name);
+    POINTERS_EQUAL(NULL, channels[0]->key);
+    CHECK(channels[1]);
+    STRCMP_EQUAL("#def", channels[1]->name);
+    POINTERS_EQUAL(NULL, channels[1]->key);
+    autojoin = irc_join_build_string (arraylist);
+    STRCMP_EQUAL("#abc,#def", autojoin);
+    free (autojoin);
+    arraylist_free (arraylist);
+
     /* server with casemapping RFC1459 */
     server = irc_server_alloc ("my_ircd");
     CHECK(server);
@@ -295,6 +359,12 @@ TEST(IrcJoin, AddChannel)
     WEE_CHECK_ADD_CHANNEL("#abc,#xyz key_abc", "#xyz", "#abc", "key_abc");
 
     WEE_CHECK_ADD_CHANNEL("#abc,#xyz,#def key_abc", "#xyz,#def", "#abc", "key_abc");
+
+    /* duplicated channel */
+    WEE_CHECK_ADD_CHANNEL("#abc,#def", "#abc,#def", "#abc", NULL);
+    WEE_CHECK_ADD_CHANNEL("#ABC,#def", "#abc,#def", "#ABC", NULL);
+    WEE_CHECK_ADD_CHANNEL("#abc,#def", "#abc,#def", "#def", NULL);
+    WEE_CHECK_ADD_CHANNEL("#abc,#DEF", "#abc,#def", "#DEF", NULL);
 }
 
 /*
@@ -323,6 +393,12 @@ TEST(IrcJoin, AddChannels)
 
     WEE_CHECK_ADD_CHANNELS("#abc,#chan1,#chan2,#xyz,#chan3 key_abc,key1,key2",
                            "#abc,#xyz,#chan2 key_abc", "#chan1,#chan2,#chan3 key1,key2");
+
+    /* duplicated channel */
+    WEE_CHECK_ADD_CHANNELS("#abc,#def", "#abc,#def", "#abc");
+    WEE_CHECK_ADD_CHANNELS("#ABC,#def", "#abc,#def", "#ABC");
+    WEE_CHECK_ADD_CHANNELS("#abc,#def", "#abc,#def", "#def");
+    WEE_CHECK_ADD_CHANNELS("#abc,#DEF", "#abc,#def", "#DEF");
 }
 
 /*
@@ -378,6 +454,10 @@ TEST(IrcJoin, SortChannels)
     WEE_CHECK_SORT_CHANNELS("#xyz,#abc key_xyz", "#xyz,#abc key_xyz");
     WEE_CHECK_SORT_CHANNELS("#xyz,#zzz,#ABC,#def,#ghi key_xyz,key_zzz",
                             "#zzz,#xyz,#ghi,#def,#ABC key_zzz,key_xyz");
+
+    /* duplicated channel */
+    WEE_CHECK_SORT_CHANNELS("#abc,#def", "#abc,#def,#abc");
+    WEE_CHECK_SORT_CHANNELS("#abc,#DEF", "#abc,#def,#abc,#def,#DEF");
 }
 
 /*
@@ -469,6 +549,42 @@ TEST(IrcJoin, AddRemoveChannelsAutojoin)
         "#abc,#xyz,#def,#ghi key_abc,key_xyz",
         CONFIG_STRING(server->options[IRC_SERVER_OPTION_AUTOJOIN]));
 
+    /* duplicated channel */
+    irc_join_add_channels_to_autojoin (server, "#abc key_abc");
+    STRCMP_EQUAL(
+        "#abc,#xyz,#def,#ghi key_abc,key_xyz",
+        CONFIG_STRING(server->options[IRC_SERVER_OPTION_AUTOJOIN]));
+
+    /* duplicated channel */
+    irc_join_add_channels_to_autojoin (server, "#xyz key_xyz");
+    STRCMP_EQUAL(
+        "#abc,#xyz,#def,#ghi key_abc,key_xyz",
+        CONFIG_STRING(server->options[IRC_SERVER_OPTION_AUTOJOIN]));
+
+    /* duplicated channel */
+    irc_join_add_channels_to_autojoin (server, "#def");
+    STRCMP_EQUAL(
+        "#abc,#xyz,#def,#ghi key_abc,key_xyz",
+        CONFIG_STRING(server->options[IRC_SERVER_OPTION_AUTOJOIN]));
+
+    /* duplicated channel */
+    irc_join_add_channels_to_autojoin (server, "#DEF");
+    STRCMP_EQUAL(
+        "#abc,#xyz,#DEF,#ghi key_abc,key_xyz",
+        CONFIG_STRING(server->options[IRC_SERVER_OPTION_AUTOJOIN]));
+
+    /* duplicated channel */
+    irc_join_add_channels_to_autojoin (server, "#ghi");
+    STRCMP_EQUAL(
+        "#abc,#xyz,#DEF,#ghi key_abc,key_xyz",
+        CONFIG_STRING(server->options[IRC_SERVER_OPTION_AUTOJOIN]));
+
+    /* duplicated channel */
+    irc_join_add_channels_to_autojoin (server, "#GHI");
+    STRCMP_EQUAL(
+        "#abc,#xyz,#DEF,#GHI key_abc,key_xyz",
+        CONFIG_STRING(server->options[IRC_SERVER_OPTION_AUTOJOIN]));
+
     irc_server_free (server);
 }