Update

after/ftplugin/javascript.vim

@@ -83,6 +83,10 @@ fu! IsStyledDefinition(lnum)
 endfu
 
 if exists('&ofu')
-  let b:prevofu=&ofu
+  if &ofu
+    " Do not keep track of previous omnifunc if it was not set in the first
+    " place
+    let b:prevofu=&ofu
+  endif
   setl omnifunc=styledcomplete#CompleteSC
 endif

after/ftplugin/typescript.vim

@@ -25,3 +25,7 @@ augroup jsx_comment
 augroup end
 
 setlocal suffixesadd+=.tsx
+if exists('g:polyglot_disabled') && index(g:polyglot_disabled, 'styled-components') != -1
+  finish
+endif
+