fix eslint

Author: sosnovsky

extension/chrome/elements/compose-modules/compose-err-module.ts

@@ -156,7 +156,7 @@ export class ComposeErrModule extends ViewModule<ComposeView> {
       // format footer the way it would be in outgoing plaintext
       footer = Xss.htmlUnescape(Xss.htmlSanitizeAndStripAllTags(this.view.footerModule.createFooterHtml(footer), '\n')).trim();
     }
-    if ((!plaintext.trim() || (footer && plaintext.trim() === footer.trim())) && !(await Ui.modal.confirm('Send empty message?'))) {
+    if ((!plaintext.trim() || plaintext.trim() === footer?.trim()) && !(await Ui.modal.confirm('Send empty message?'))) {
       throw new ComposerResetBtnTrigger();
     }
   };

extension/chrome/elements/compose-modules/compose-quote-module.ts

@@ -177,7 +177,7 @@ export class ComposeQuoteModule extends ViewModule<ComposeView> {
     });
     if (decryptRes.success) {
       return decryptRes.content.toUtfStr();
-    } else if (decryptRes.error && decryptRes.error.type === DecryptErrTypes.needPassphrase) {
+    } else if (decryptRes.error?.type === DecryptErrTypes.needPassphrase) {
       if (Catch.isThunderbirdMail() && this.view.useFullScreenSecureCompose) {
         await Time.sleep(2300);
       }

extension/chrome/elements/compose-modules/compose-storage-module.ts

@@ -108,7 +108,7 @@ export class ComposeStorageModule extends ViewModule<ComposeView> {
     const kis = await KeyStore.get(this.view.acctEmail);
     for (const ki of kis) {
       const pp = await PassphraseStore.get(this.view.acctEmail, ki, true);
-      if (pp && pwd.toLowerCase() === pp.toLowerCase()) {
+      if (pwd.toLowerCase() === pp?.toLowerCase()) {
         return true;
       }
       // check whether this pwd unlocks the ki

extension/js/content_scripts/webmail/thunderbird/thunderbird-element-replacer.ts

@@ -59,7 +59,7 @@ export class ThunderbirdElementReplacer extends WebmailElementReplacer {
           } else {
             const decryptErr = result as DecryptError;
             let decryptionErrorMsg = '';
-            if (decryptErr.error && decryptErr.error.type === DecryptErrTypes.needPassphrase) {
+            if (decryptErr.error?.type === DecryptErrTypes.needPassphrase) {
               const acctEmail = String(await BrowserMsg.send.bg.await.thunderbirdGetCurrentUser());
               const longids = decryptErr.longids.needPassphrase.join(',');
               decryptionErrorMsg = `decrypt error: private key needs to be unlocked by your passphrase.`;