select.lua: strip filename from the display of external track titles

It doesn't make much sense to display them, streamline the display
as much as possible and avoid excessively long external titles

player/lua/select.lua

@@ -99,10 +99,23 @@ local function format_flags(track)
 end
 
 local function format_track(track)
+    local title = track.title or ""
+    local filename = mp.get_property_native("filename/no-ext", "")
+                    :gsub("[%(%)%.%%%+%-%*%?%[%]%^%$]", "%%%0")
     local bitrate = track["demux-bitrate"] or track["hls-bitrate"]
 
+    if track.external and title ~= "" then
+        local extension = title:match("%.([^%.]+)$")
+        if filename ~= "" and extension then
+            title = title:gsub(filename .. "%.?", "")
+        end
+        if track.lang and title:lower() == track.lang:lower() .. "." .. extension:lower() then
+            title = extension:lower()
+        end
+    end
+
     return (track.selected and "●" or "○") ..
-        (track.title and " " .. track.title or "") ..
+        (title ~= "" and " " .. title or "") ..
         " (" .. (
             (track.lang and track.lang .. " " or "") ..
             (track.codec and track.codec .. " " or "") ..