diff --git a/templates/repo/issue/view_content/sidebar.tmpl b/templates/repo/issue/view_content/sidebar.tmpl
index d778beee4e..a8f0ed5ab4 100644
--- a/templates/repo/issue/view_content/sidebar.tmpl
+++ b/templates/repo/issue/view_content/sidebar.tmpl
@@ -290,18 +290,16 @@
 
 		<div class="ui divider"></div>
 
-		<div class="ui participants">
+		{{if .Participants}}
 			<span class="text"><strong>{{.i18n.Tr "repo.issues.num_participants" .NumParticipants}}</strong></span>
-			<div>
+			<div class="ui list df fw">
 				{{range .Participants}}
-					<a {{if gt .ID 0}}href="{{.HomeLink}}"{{end}}>
-						<div class="ui poping up" data-content="{{.GetDisplayName}}" data-position="top center" data-variation="small inverted">
-							{{avatar .}}
-						</div>
+					<a class="ui poping up" {{if gt .ID 0}}href="{{.HomeLink}}"{{end}} data-content="{{.GetDisplayName}}" data-position="top center" data-variation="small inverted">
+						{{avatar . 28 "my-1 mr-2"}}
 					</a>
 				{{end}}
 			</div>
-		</div>
+		{{end}}
 
 		{{if and $.IssueWatch (not .Repository.IsArchived)}}
 			<div class="ui divider"></div>
@@ -330,7 +328,7 @@
 				<div class="ui divider"></div>
 				<div class="ui timetrack">
 					<span class="text"><strong>{{.i18n.Tr "repo.issues.tracker"}}</strong></span>
-					<div>
+					<div class="mt-3">
 						<form method="POST" action="{{$.RepoLink}}/issues/{{.Issue.Index}}/times/stopwatch/toggle" id="toggle_stopwatch_form">
 							{{$.CsrfTokenHtml}}
 						</form>
@@ -372,11 +370,11 @@
 			{{end}}
 			{{if gt (len .WorkingUsers) 0}}
 				<div class="ui divider"></div>
-				<div class="ui participants comments">
+				<div class="ui comments">
 					<span class="text"><strong>{{.i18n.Tr "repo.issues.time_spent_from_all_authors"  ($.Issue.TotalTrackedTime | Sec2Time) | Safe}}</strong></span>
 					<div>
 						{{range $user, $trackedtime := .WorkingUsers}}
-							<div class="comment">
+							<div class="comment mt-3">
 								<a class="avatar">
 									{{avatar $user}}
 								</a>
diff --git a/web_src/less/_repository.less b/web_src/less/_repository.less
index 9925a79202..b4cff3490d 100644
--- a/web_src/less/_repository.less
+++ b/web_src/less/_repository.less
@@ -1189,13 +1189,6 @@
       }
     }
 
-    .ui.participants {
-      img {
-        margin-top: 5px;
-        margin-right: 5px;
-      }
-    }
-
     .ui.depending {
       .item.is-closed {
         .title {