diff --git a/.eslintrc.json b/.eslintrc.json
index 4018b46..012e888 100644
--- a/.eslintrc.json
+++ b/.eslintrc.json
@@ -248,7 +248,7 @@
       "never"
     ],
     "prefer-arrow/prefer-arrow-functions": [
-      "error",
+      "warn",
       {
         "allowStandaloneDeclarations": true
       }
diff --git a/esbuild.js b/esbuild.js
index 535b41a..8535129 100644
--- a/esbuild.js
+++ b/esbuild.js
@@ -2,7 +2,7 @@ const path = require('path')
 const fs = require('fs')
 const esbuild = require('esbuild')
 const rmrf = require('rimraf')
-const { parse: ftl } = require('@fluent/syntax')
+const { parse: parseftl } = require('@fluent/syntax')
 
 rmrf.sync('gen')
 
@@ -21,8 +21,8 @@ const ftl = {
       const text = await fs.promises.readFile(args.path, 'utf-8')
 
       const l10n = {}
-      for (const message of ftl(text).body) {
-        l10n[message.id.name] = message.value.elements.map{|element| element.value}.join('')
+      for (const message of parseftl(text).body) {
+        l10n[message.id.name] = message.value.elements.map(element => element.value).join('')
       }
 
       return {
diff --git a/lib.ts b/lib.ts
index 7ccb9da..096f14c 100644
--- a/lib.ts
+++ b/lib.ts
@@ -1,5 +1,6 @@
 declare const Zotero: any
 declare const Components: any
+declare const Services: any
 
 import l10n = require('./locale/en-US/zotero-edtechhub.ftl')
 
@@ -153,8 +154,8 @@ function zotero_itemmenu_popupshowing() {
   // bluebird promise has status
   const pending = (EdTechHub.ready as any).isPending()
   const hidden = pending || !selected.find(item => item.isRegularItem()) // eslint-disable-line @typescript-eslint/no-unsafe-return
-  for (const elt of Array.from(doc.getElementsByClassName('edtechhub-zotero-itemmenu-regularitem'))) {
-    (elt as any).hidden = hidden
+  for (const elt of Array.from(doc.getElementsByClassName('edtechhub-zotero-itemmenu-regularitem') as HTMLElement[])) {
+    elt.hidden = hidden
   }
 
   doc.getElementById('edtechhub-duplicate-attachment').hidden =
@@ -238,14 +239,14 @@ class EdTechHubMain {
       XUL: 'http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul',
       HTML: 'http://www.w3.org/1999/xhtml',
     }
-    function create(name: string, attrs: Record<string, number | string | Handler | HTMLElement[]> = {}): HTMLElement {
+    function create(name: string, attrs: Record<string, number | string | Function | HTMLElement[]> = {}): HTMLElement {
       const children: HTMLElement[] = (attrs.$ as unknown as HTMLElement[]) || []
       delete attrs.$
 
       const namespace = name.startsWith('html:') ? NAMESPACE.HTML : NAMESPACE.XUL
       name = name.replace('html:', '')
 
-      const elt: HTMLElement = is7
+      const elt: HTMLElement = Zotero.platformMajorVersion >= 102 // eslint-disable-line @typescript-eslint/no-magic-numbers
         ? doc[ namespace === NAMESPACE.XUL ? 'createXULElement' : 'createElement' ](name) as HTMLElement
         : doc.createElementNS(namespace, name) as HTMLElement
       attrs.class = `edtechhub ${attrs.class || ''}`.trim()
@@ -283,7 +284,7 @@ class EdTechHubMain {
 
     win.addEventListener('unload', _event => {
       doc.getElementById('zotero-itemmenu').removeEventListener('popupshowing', zotero_itemmenu_popupshowing, false)
-      for (const elt of Array.from(doc.getElementsByClassName('edtechhub'))) {
+      for (const elt of Array.from(doc.getElementsByClassName('edtechhub') as HTMLElement[])) {
         elt.remove()
       }
     }, false)
@@ -292,37 +293,37 @@ class EdTechHubMain {
     itemmenu.appendChild(create('menuseparator'))
     itemmenu.appendChild(create('menuitem', {
       class: 'edtechhub-zotero-itemmenu-regularitem',
-      label: l10n['edtechhub_Bjoern2A_BjoernCitationStringTagged'],
-      oncommand: () => Zotero.EdTechHub.run('copyToClipboard', '4ec4a50b-e979-448f-af4c-e5b46d1a3b03')
+      label: l10n.edtechhub_Bjoern2A_BjoernCitationStringTagged,
+      oncommand: () => void Zotero.EdTechHub.run('copyToClipboard', '4ec4a50b-e979-448f-af4c-e5b46d1a3b03'),
     }))
     itemmenu.appendChild(create('menuitem', {
       class: 'edtechhub-zotero-itemmenu-regularitem',
-      label: l10n['edtechhub_Bjoern2C_BjoernCitationStringTagged'],
-      oncommand: () => Zotero.EdTechHub.run('copyToClipboard', 'fe1c68d8-aa8e-11eb-85c1-1799e2c1b06e')
+      label: l10n.edtechhub_Bjoern2C_BjoernCitationStringTagged,
+      oncommand: () => void Zotero.EdTechHub.run('copyToClipboard', 'fe1c68d8-aa8e-11eb-85c1-1799e2c1b06e'),
     }))
     itemmenu.appendChild(create('menuitem', {
       class: 'edtechhub-zotero-itemmenu-regularitem',
-      label: l10n['edtechhub_Bjoern7_ETHref'],
-      oncommand: () => Zotero.EdTechHub.run('copyToClipboard', 'ba5f8764-3966-11ea-9cd5-5b52329a4e4c')
+      label: l10n.edtechhub_Bjoern7_ETHref,
+      oncommand: () => void Zotero.EdTechHub.run('copyToClipboard', 'ba5f8764-3966-11ea-9cd5-5b52329a4e4c'),
     }))
     itemmenu.appendChild(create('menuitem', {
       class: 'edtechhub-zotero-itemmenu-regularitem',
       label: l10n['edtechhub_assign-key'],
-      oncommand: () => Zotero.EdTechHub.run('assignKey')
+      oncommand: () => void Zotero.EdTechHub.run('assignKey'),
     }))
     itemmenu.appendChild(create('menuitem', {
-      class: 'edtechhub-zotero-itemmenu-regularitem', 
+      class: 'edtechhub-zotero-itemmenu-regularitem',
       label: l10n['edtechhub_save-to-note'],
-      oncommand: () => Zotero.EdTechHub.run('saveToNote')
+      oncommand: () => void Zotero.EdTechHub.run('saveToNote'),
     }))
     itemmenu.appendChild(create('menuitem', {
       id: 'edtechhub-duplicate-attachment',
       label: l10n['edtechhub_duplicate-attachment'],
-      oncommand: () => Zotero.EdTechHub.run('duplicateAttachment')
+      oncommand: () => void Zotero.EdTechHub.run('duplicateAttachment'),
     }))
   }
 
-  startup() {
+  async startup() {
     const ready = Zotero.Promise.defer()
     this.ready = ready.promise
 
@@ -435,7 +436,7 @@ class EdTechHubMain {
     const doc = win.document
 
     doc.getElementById('zotero-itemmenu').removeEventListener('popupshowing', zotero_itemmenu_popupshowing, false)
-    for (const elt of Array.from(doc.getElementsByClassName('edtechhub'))) {
+    for (const elt of Array.from(doc.getElementsByClassName('edtechhub') as HTMLElement[])) {
       elt.remove()
     }
   }