feat(xo-web/backup): add placeholder to report recipients input (#5051)

Fixes #5035

packages/xo-web/src/common/intl/messages.js

@@ -77,6 +77,7 @@ const messages = {
   withMemory: 'With memory',
   offline: 'Offline',
   noLicenseAvailable: 'No license available',
+  emailPlaceholderExample: 'Email address, e.g.: it@company.net',
 
   // ----- Modals -----
   alertOk: 'OK',

packages/xo-web/src/xo-app/backup/new/index.js

@@ -104,8 +104,9 @@ const ReportRecipients = decorate([
       disabledAddButton: ({ recipient }) => recipient === '',
     },
   }),
+  injectIntl,
   injectState,
-  ({ effects, recipients, remove, state }) => (
+  ({ effects, intl: { formatMessage }, recipients, remove, state }) => (
     <div>
       <FormGroup>
         <label htmlFor={state.inputId}>
@@ -117,6 +118,8 @@ const ReportRecipients = decorate([
             name='recipient'
             onChange={effects.linkState}
             onKeyDown={effects.onKeyDown}
+            placeholder={formatMessage(messages.emailPlaceholderExample)}
+            type='email'
             value={state.recipient}
           />
           <span className='input-group-btn'>