IE doesn't like negated empty character classes.

Changing this to match the "dot" character class wouldn't work, though, because . doesn't match invisible whitespace like newlines, so we need to include those specifically.

src/handlebars.l

@@ -3,8 +3,8 @@
 
 %%
 
-[^]*?/("{{")                 { this.begin("mu"); if (yytext) return 'CONTENT'; }
-[^]+                         { return 'CONTENT'; }
+(.|\n|\r)*?/("{{")                 { this.begin("mu"); if (yytext) return 'CONTENT'; }
+(.|\n|\r)+                         { return 'CONTENT'; }
 
 <mu>"{{>"                    { return 'OPEN_PARTIAL'; }
 <mu>"{{#"                    { return 'OPEN_BLOCK'; }