--- a/options/options.js	Tue Nov 17 15:31:50 2020 +0100
+++ b/options/options.js	Sat Apr 17 23:07:57 2021 +0200
@@ -29,24 +29,6 @@
         feedReadersForm.elements['remove'].textContent =
                 browser.i18n.getMessage('feedReaderRemoveButton');
         feedReadersForm.addEventListener('change', this);
-        // FIXME remove once the Firefox ESR release supports SubmitEvent
-        if (typeof SubmitEvent === 'undefined') {
-            for (let element of [
-                        feedReadersForm.elements['move-up'],
-                        feedReadersForm.elements['move-down'],
-                        feedReadersForm.elements['remove']
-                    ]) {
-                element.addEventListener('click', ev => {
-                    ev.preventDefault();
-                    let submitEvent = new Event('submit', {
-                        'bubbles':true,
-                        'cancelable':true
-                    });
-                    submitEvent.submitter = ev.target;
-                    feedReadersForm.dispatchEvent(submitEvent)
-                });
-            }
-        }
 
         let addFeedReaderForm = document.forms['add-feed-reader'];
         addFeedReaderForm.elements['add'].textContent =