diff --git a/lua/outline/highlight.lua b/lua/outline/highlight.lua
index 514c1f3..2fcddb1 100644
--- a/lua/outline/highlight.lua
+++ b/lua/outline/highlight.lua
@@ -9,13 +9,17 @@ local M = {
 ---Clear all highlights in buffer
 ---@param bufnr integer
 function M.clear_all_ns(bufnr)
-  vim.api.nvim_buf_clear_namespace(bufnr, -1, 0, -1)
+  if vim.api.nvim_buf_is_valid(bufnr) then
+      vim.api.nvim_buf_clear_namespace(bufnr, -1, 0, -1)
+  end
 end
 
 ---Clear hover highlights in buffer
 ---@param bufnr integer
 function M.clear_hovers(bufnr)
-  vim.api.nvim_buf_clear_namespace(bufnr, M.ns.hover, 0, -1)
+  if vim.api.nvim_buf_is_valid(bufnr) then
+    vim.api.nvim_buf_clear_namespace(bufnr, M.ns.hover, 0, -1)
+  end
 end
 
 ---Add single hover highlights
diff --git a/lua/outline/view.lua b/lua/outline/view.lua
index 6067e77..a790d2a 100644
--- a/lua/outline/view.lua
+++ b/lua/outline/view.lua
@@ -87,13 +87,15 @@ end
 ---Replace all lines in buffer with given new `lines`
 ---@param lines string[]
 function View:rewrite_lines(lines)
-  vim.api.nvim_buf_set_option(self.buf, 'modifiable', true)
-  vim.api.nvim_buf_set_lines(self.buf, 0, -1, false, lines)
-  vim.api.nvim_buf_set_option(self.buf, 'modifiable', false)
+  if vim.api.nvim_buf_is_valid(self.buf) then
+    vim.api.nvim_buf_set_option(self.buf, 'modifiable', true)
+    vim.api.nvim_buf_set_lines(self.buf, 0, -1, false, lines)
+    vim.api.nvim_buf_set_option(self.buf, 'modifiable', false)
+  end
 end
 
 function View:clear_all_ns()
-  highlight.clear_all_ns(self.buf)
+  pcall(function() highlight.clear_all_ns(self.buf) end)
 end
 
 ---Ensure all existing highlights are already cleared before calling!