gitea/templates/repo/issue/sidebar/due_date.tmpl

<div class="divider"></div>
<span class="text"><strong>{{ctx.Locale.Tr "repo.issues.due_date"}}</strong></span>
<div class="ui form tw-mt-2">
	{{if .Issue.DeadlineUnix}}
		<div class="tw-flex tw-justify-between tw-items-center tw-gap-2">
			<div class="due-date {{if .Issue.IsOverdue}}text red{{end}}" {{if .Issue.IsOverdue}}data-tooltip-content="{{ctx.Locale.Tr "repo.issues.due_date_overdue"}}"{{end}}>
				{{svg "octicon-calendar"}} {{DateUtils.AbsoluteLong .Issue.DeadlineUnix}}
			</div>
			<div class="flex-text-block">
				{{if and .HasIssuesOrPullsWritePermission (not .Repository.IsArchived)}}
					<a class="issue-due-edit muted" data-tooltip-content="{{ctx.Locale.Tr "repo.issues.due_date_form_edit"}}">{{svg "octicon-pencil"}}</a>
					<a class="issue-due-remove muted" data-tooltip-content="{{ctx.Locale.Tr "repo.issues.due_date_form_remove"}}">{{svg "octicon-trash"}}</a>
				{{end}}
			</div>
		</div>
	{{else}}
		{{ctx.Locale.Tr "repo.issues.due_date_not_set"}}
	{{end}}

	{{if and .HasIssuesOrPullsWritePermission (not .Repository.IsArchived)}}
		<form class="ui fluid action input issue-due-form form-fetch-action tw-mt-2 {{if .Issue.DeadlineUnix}}tw-hidden{{end}}"
					method="post" action="{{AppSubUrl}}/{{PathEscape .Repository.Owner.Name}}/{{PathEscape .Repository.Name}}/issues/{{.Issue.Index}}/deadline"
		>
			{{$.CsrfTokenHtml}}
			<input required type="date" name="deadline" placeholder="{{ctx.Locale.Tr "repo.issues.due_date_form"}}" {{if .Issue.DeadlineUnix}}value="{{.Issue.DeadlineUnix.FormatDate}}"{{end}}>
			<button class="ui icon button">{{Iif .Issue.DeadlineUnix (svg "octicon-pencil") (svg "octicon-plus")}}</button>
		</form>
	{{end}}
</div>