Replace is… an interesting function

Fixes #38

Gruntfile.js

@@ -124,7 +124,8 @@ module.exports = function (grunt) {
         // we'd need to grab it from ff... but that may have already been filled
         let content = grunt.file.read("dist/modulesjs/content_script.js");
 
-        content = content.replace('return "placeholder";', injected);
+        // escape the dollar sign to avoid replacements: https://es.stackoverflow.com/a/267800/11272
+        content = content.replace('return "placeholder";', injected.replace(/\$/g, "$$$$"));
 
         grunt.file.write("dist/ff/content_script.js", content);
         grunt.file.delete("dist/ff/injected_script.js");

src/plugins/baseMessageModifierPlugin.ts

@@ -64,10 +64,12 @@ export default abstract class BaseMessageModifierPlugin extends BasePlugin {
                 text = this.doChange(text);
 
                 for (let i = 0; i < code.length; i++) {
-                    text = text.replace(`||refinedCode${i}||`, code[i]);
+                    // escape the dollar sign to avoid replacements: https://es.stackoverflow.com/a/267800/11272
+                    text = text.replace(`||refinedCode${i}||`, code[i].replace(/\$/g, "$$$$"));
                 }
                 for (let i = 0; i < blocks.length; i++) {
-                    text = text.replace(`||refinedBlock${i}||`, blocks[i]);
+                    // escape the dollar sign to avoid replacements: https://es.stackoverflow.com/a/267800/11272
+                    text = text.replace(`||refinedBlock${i}||`, blocks[i].replace(/\$/g, "$$$$"));
                 }
 
                 e.set(key, text);