diff --git a/service/dap/server.go b/service/dap/server.go
index 19c1856b4a..08a3b2e7d1 100644
--- a/service/dap/server.go
+++ b/service/dap/server.go
@@ -1800,7 +1800,7 @@ func (s *Session) onThreadsRequest(request *dap.ThreadsRequest) {
 			if g.Thread != nil && g.Thread.ThreadID() != 0 {
 				thread = fmt.Sprintf(" (Thread %d)", g.Thread.ThreadID())
 			}
-			labels := ""
+			var labels strings.Builder
 			if len(g.Labels()) > 0 {
 				var keys []string
 				for k := range g.Labels() {
@@ -1808,13 +1808,13 @@ func (s *Session) onThreadsRequest(request *dap.ThreadsRequest) {
 				}
 				sort.Strings(keys)
 				for _, k := range keys {
-					labels += fmt.Sprintf(" %s=%s", k, g.Labels()[k])
+					fmt.Fprintf(&labels, " %s=%s", k, g.Labels()[k])
 				}
 			}
 			// File name and line number are communicated via `stackTrace`
 			// so no need to include them here.
 			loc := g.UserCurrent()
-			threads[i].Name = fmt.Sprintf("%s[Go %d%s] %s%s", selected, g.ID, labels, fnName(&loc), thread)
+			threads[i].Name = fmt.Sprintf("%s[Go %d%s] %s%s", selected, g.ID, labels.String(), fnName(&loc), thread)
 			threads[i].Id = int(g.ID)
 		}
 	}