diff --git a/README.md b/README.md
index e516687..acdc97b 100644
--- a/README.md
+++ b/README.md
@@ -76,7 +76,7 @@ The available options:
   - `{ "80", "100" }`
 - `disabled_filetypes` (table of strings) : the `colorcolumn` will be disabled under the filetypes in this table
   - `{ "help", "text", "markdown" }` (default)
-  - `{ "NvimTree", "Lazy", "mason", "help" }`
+  - `{ "NvimTree", "lazy", "mason", "help" }`
 - `scope` (strings): the plugin only checks whether the lines within scope exceed colorcolumn
   - `"file"` (default): current file
   - `"window"`: visible part of current window
diff --git a/lua/smartcolumn.lua b/lua/smartcolumn.lua
index 85566ad..3b55c7e 100644
--- a/lua/smartcolumn.lua
+++ b/lua/smartcolumn.lua
@@ -54,14 +54,18 @@ local function update()
    for _, win in pairs(wins) do
       local buf = vim.api.nvim_win_get_buf(win)
       if buf == current_buf then
-         if exceed(buf, win, min_colorcolumn) then
-            if type(colorcolumns) == "table" then
-               vim.wo[win].colorcolumn = table.concat(colorcolumns, ",")
+         local current_state = exceed(buf, win, min_colorcolumn)
+         if current_state ~= vim.b.prev_state then
+            vim.b.prev_state = current_state
+            if current_state then
+               if type(colorcolumns) == "table" then
+                  vim.wo[win].colorcolumn = table.concat(colorcolumns, ",")
+               else
+                  vim.wo[win].colorcolumn = colorcolumns
+               end
             else
-               vim.wo[win].colorcolumn = colorcolumns
+               vim.wo[win].colorcolumn = nil
             end
-         else
-            vim.wo[win].colorcolumn = nil
          end
       end
    end