Check features are available before using them

plugin/settings.vim

@@ -7,10 +7,14 @@ set mouse=a
 " TODO: whichwrap=b,h,l,s,<,>,[,],~
 
 " Don't show completeopt preview buffer
-set completeopt-=preview
+if has('insert_expand')
+  set completeopt-=preview
+endif
 
 " Set window title to titlestring
-set title
+if has('title')
+  set title
+endif
 
 " Don't show mode in command line
 set noshowmode
@@ -23,10 +27,16 @@ set relativenumber
 set scrolloff=8
 
 " Turn backup off
-set nobackup nowritebackup noswapfile
+set nobackup noswapfile
+if has('writebackup')
+  set nowritebackup
+endif
 
 " Wrap to whole words
-set wrap linebreak nolist
+set wrap nolist
+if has('linebreak')
+  set linebreak
+endif
 
 " Don't add 2 spaces after end of sentence
 set nojoinspaces
@@ -47,13 +57,20 @@ set ignorecase smartcase
 set hidden
 
 " Open new splits on the other side of the axis
-set splitbelow splitright
+if has('windows')
+  set splitbelow
+endif
+if has('vertsplit')
+  set splitright
+endif
 
 " Indicates a fast terminal connection
 set ttyfast
 
 " Set syntax as default fold method
-set foldmethod=syntax foldlevel=20
+if has('folding')
+  set foldmethod=syntax foldlevel=20
+endif
 
 " Automatically write changes to files
 set autowrite