diff --git a/.changeset/wicked-crews-provide.md b/.changeset/wicked-crews-provide.md
new file mode 100644
index 0000000000..39100b58cd
--- /dev/null
+++ b/.changeset/wicked-crews-provide.md
@@ -0,0 +1,5 @@
+---
+'@openproject/primer-view-components': patch
+---
+
+Do not overwrite custom data attributes
diff --git a/app/components/primer/open_project/sub_header.rb b/app/components/primer/open_project/sub_header.rb
index 4c982c67b0..df6262ed4f 100644
--- a/app/components/primer/open_project/sub_header.rb
+++ b/app/components/primer/open_project/sub_header.rb
@@ -47,22 +47,16 @@ class SubHeader < Primer::Component
         system_arguments[:input_width] ||= :medium
 
         system_arguments[:data] ||= {}
-        system_arguments[:data][:target]= "sub-header.filterInput"
+        system_arguments[:data] = merge_data(
+         system_arguments,
+           { data: { target: "sub-header.filterInput" } }
+         )
 
         system_arguments[:show_clear_button] = true if system_arguments[:show_clear_button].nil?
 
         if system_arguments[:show_clear_button]
-          system_arguments[:data] = merge_data(
-            system_arguments,
-            {
-              data: {
-                action: <<~JS
-                  input:sub-header#toggleFilterInputClearButton
-                  focus:sub-header#toggleFilterInputClearButton
-                JS
-              }
-            }
-          )
+          system_arguments[:data][:action] ||= ""
+          system_arguments[:data][:action] += " input:sub-header#toggleFilterInputClearButton focus:sub-header#toggleFilterInputClearButton"
         end
 
         @mobile_filter_trigger = Primer::Beta::IconButton.new(icon: system_arguments[:leading_visual][:icon],
diff --git a/test/components/primer/open_project/sub_header_test.rb b/test/components/primer/open_project/sub_header_test.rb
index dbcb6f1f38..1026caeeca 100644
--- a/test/components/primer/open_project/sub_header_test.rb
+++ b/test/components/primer/open_project/sub_header_test.rb
@@ -106,8 +106,7 @@ def test_renders_a_clear_button_when_show_clear_button_is_set
     assert_selector(".SubHeader")
     assert_selector(
       ".SubHeader-filterInput"\
-      "[data-action=\"input:sub-header#toggleFilterInputClearButton\n"\
-                     "focus:sub-header#toggleFilterInputClearButton\n\"]"
+      "[data-action=\" input:sub-header#toggleFilterInputClearButton focus:sub-header#toggleFilterInputClearButton\"]"
     )
     assert_selector(".FormControl-input-trailingAction[data-action=\"click:primer-text-field#clearContents\"]")
   end
@@ -126,8 +125,7 @@ def test_does_not_render_input_events_when_show_clear_button_is_not_set
     assert_selector(".SubHeader-filterInput")
     assert_no_selector(
       ".SubHeader-filterInput"\
-      "[data-action=\"input:sub-header#toggleFilterInputClearButton\n"\
-                     "focus:sub-header#toggleFilterInputClearButton\n\"]"
+      "[data-action=\" input:sub-header#toggleFilterInputClearButton focus:sub-header#toggleFilterInputClearButton\"]"
     )
     assert_no_selector(".FormControl-input-trailingAction[data-action=\"click:primer-text-field#clearContents\"]")
   end