diff --git a/config_webrx.py b/config_webrx.py
index a4a6fdff..d166045f 100644
--- a/config_webrx.py
+++ b/config_webrx.py
@@ -66,6 +66,7 @@ sdrhu_public_listing = False
 dsp_plugin="csdr"
 fft_fps=9
 fft_size=4096
+
 #samp_rate = 2048000
 samp_rate = 250000
 
@@ -112,5 +113,7 @@ client_audio_buffer_size = 5
 start_freq = center_freq
 start_mod = "nfm" #nfm, am, lsb, usb, cw
 
+fft_max_seen=0 # N*200 pixels vertically. Set 0 to never clear on-screen history.
+
 iq_server_port = 4951
 # (if ncat is not available on your system, rtl_mus will be used, thus you will have to set the same port as "my_listening_port" in config_rtl.py as well)
diff --git a/htdocs/index.wrx b/htdocs/index.wrx
index 5cc9fe57..cae74966 100644
--- a/htdocs/index.wrx
+++ b/htdocs/index.wrx
@@ -30,6 +30,7 @@
 			var audio_buffering_fill_to=%[AUDIO_BUFSIZE];
 			var starting_mod = "%[START_MOD]";
 			var starting_offset_frequency = %[START_OFFSET_FREQ];
+			var fft_max_seen = %[FFT_MAX_SEEN];
 		</script>
 		<script src="sdr.js"></script>
 		<script src="openwebrx.js"></script>
diff --git a/htdocs/openwebrx.js b/htdocs/openwebrx.js
index 7ea1c2ea..3ff74b2b 100644
--- a/htdocs/openwebrx.js
+++ b/htdocs/openwebrx.js
@@ -1564,6 +1564,7 @@ function add_canvas()
 	new_canvas.addEventListener("mousedown", canvas_mousedown, false);
 	new_canvas.addEventListener("wheel",canvas_mousewheel, false);
 	canvases.push(new_canvas);
+	if(fft_max_seen && canvases.length>fft_max_seen) canvas_container.removeChild(canvases.shift());
 }
 
 function init_canvas_container()
diff --git a/openwebrx.py b/openwebrx.py
index 32772830..eb0f1f4f 100755
--- a/openwebrx.py
+++ b/openwebrx.py
@@ -433,8 +433,6 @@ class WebRXHandler(BaseHTTPRequestHandler):
 							if comm_time_counter % 16 == 0:
 								myclient.last_comm_time=time.time()
 
-						print myclient.last_comm_time, comm_time_counter
-
 						# ========= process commands =========
 						while True:
 							rdata=rxws.recv(self, False)
@@ -550,6 +548,7 @@ class WebRXHandler(BaseHTTPRequestHandler):
 						("%[RX_DEVICE]",cfg.receiver_device),
 						("%[AUDIO_BUFSIZE]",str(cfg.client_audio_buffer_size)),
 						("%[START_OFFSET_FREQ]",str(cfg.start_freq-cfg.center_freq)),
+						("%[FFT_MAX_SEEN]",str(cfg.fft_max_seen)),
 						("%[START_MOD]",cfg.start_mod)
 					)
 					for rule in replace_dictionary: