diff --git a/assets/javascripts/discourse/components/topic-level-assign-menu.js b/assets/javascripts/discourse/components/topic-level-assign-menu.js
index 7e4d2b1..4425c42 100644
--- a/assets/javascripts/discourse/components/topic-level-assign-menu.js
+++ b/assets/javascripts/discourse/components/topic-level-assign-menu.js
@@ -105,14 +105,6 @@ function avatarHtml(user, size, classes) {
   });
 }
 
-// function nameOrUsername() {
-//   if (this.siteSettings.prioritize_full_name_in_ux) {
-//     topic.assigned_to_user?.name || topic.assigned_to_user?.username;
-//   } else {
-//     topic.assigned_to_user?.username;
-//   }
-// }
-
 function extractPostId(buttonId) {
   // buttonId format is "unassign-from-post-${postId}"
   const start = buttonId.lastIndexOf("-") + 1;
diff --git a/assets/javascripts/discourse/initializers/extend-for-assigns.js b/assets/javascripts/discourse/initializers/extend-for-assigns.js
index b8f86a4..9705337 100644
--- a/assets/javascripts/discourse/initializers/extend-for-assigns.js
+++ b/assets/javascripts/discourse/initializers/extend-for-assigns.js
@@ -479,7 +479,13 @@ function initialize(api) {
             assignedPath = `/t/${topic.id}`;
           }
           const icon = iconHTML(assignee.username ? "user-plus" : "group-plus");
-          const name = assignee.username || assignee.name;
+          let name;
+          if (siteSettings.prioritize_full_name_in_ux) {
+            name = assignee.name;
+          } else {
+            name = assignee.username;
+          }
+
           const tagName = params.tagName || "a";
           const href =
             tagName === "a"
@@ -572,14 +578,19 @@ function initialize(api) {
           })
         )}</span>`;
       };
-
+      let displayedName = "";
       if (assignedToUser) {
+        if (this.siteSettings.prioritize_full_name_in_ux) {
+          displayedName = assignedToUser.name;
+        } else {
+          displayedName = assignedToUser.username;
+        }
         assigneeElements.push(
           h(
             "span.assignee",
             new RawHtml({
               html: assignedHtml(
-                assignedToUser.username,
+                displayedName,
                 assignedToUserPath(assignedToUser),
                 "user"
               ),
@@ -601,10 +612,18 @@ function initialize(api) {
           )
         );
       }
+
       if (indirectlyAssignedTo) {
         Object.keys(indirectlyAssignedTo).map((postId) => {
           const assignee = indirectlyAssignedTo[postId].assigned_to;
           const postNumber = indirectlyAssignedTo[postId].post_number;
+
+          if (this.siteSettings.prioritize_full_name_in_ux) {
+            displayedName = assignee.name;
+          } else {
+            displayedName = assignee.username;
+          }
+
           assigneeElements.push(
             h("span.assignee", [
               h(
@@ -617,14 +636,14 @@ function initialize(api) {
                 },
                 i18n("discourse_assign.assign_post_to_multiple", {
                   post_number: postNumber,
-                  username: assignee.username || assignee.name,
+                  username: displayedName,
                 })
               ),
             ])
           );
         });
       }
-      console.log(assigneeElements);
+
       if (!isEmpty(assigneeElements)) {
         return h("p.assigned-to", [
           assignedToUser ? iconNode("user-plus") : iconNode("group-plus"),
diff --git a/assets/javascripts/discourse/models/assignment.js b/assets/javascripts/discourse/models/assignment.js
index 706ddcf..67b0086 100644
--- a/assets/javascripts/discourse/models/assignment.js
+++ b/assets/javascripts/discourse/models/assignment.js
@@ -6,7 +6,6 @@ export class Assignment extends EmberObject {
     const assignment = new Assignment();
     assignment.id = 0;
     assignment.username = topic.assigned_to_user?.username;
-    assignment.name = topic.assigned_to_user?.name;
     assignment.groupName = topic.assigned_to_group?.name;
     assignment.status = topic.assignment_status;
     assignment.note = topic.assignment_note;
diff --git a/spec/system/assign_post_spec.rb b/spec/system/assign_post_spec.rb
new file mode 100644
index 0000000..2114ccc
--- /dev/null
+++ b/spec/system/assign_post_spec.rb
@@ -0,0 +1,184 @@
+# frozen_string_literal: true
+
+describe "Assign | Assigning posts", type: :system do
+  let(:topic_page) { PageObjects::Pages::Topic.new }
+  let(:assign_modal) { PageObjects::Modals::Assign.new }
+  fab!(:staff_user) { Fabricate(:user, groups: [Group[:staff]]) }
+  fab!(:admin)
+  fab!(:topic)
+  fab!(:post1) { Fabricate(:post, topic: topic) }
+  fab!(:post2) { Fabricate(:post, topic: topic) }
+
+  before do
+    SiteSetting.assign_enabled = true
+
+    # # The system tests in this file are flaky and auth token related so turning this on
+    # SiteSetting.verbose_auth_token_logging = true
+
+    sign_in(admin)
+  end
+
+  describe "with open topic" do
+    before { SiteSetting.prioritize_full_name_in_ux = false }
+
+    it "can assign and unassign" do
+      visit "/t/#{topic.id}"
+
+      topic_page.click_assign_post(post2)
+      assign_modal.assignee = staff_user
+      assign_modal.confirm
+
+      expect(assign_modal).to be_closed
+
+      expect(topic_page).to have_assigned_post(user: staff_user, at_post: 3)
+
+      expect(topic_page.find_post_assign(post1.post_number)).to have_content(staff_user.username)
+      expect(topic_page.find_post_assign(post2.post_number)).to have_content(staff_user.username)
+
+      visit "/t/#{topic.id}"
+
+      topic_page.click_unassign_post(post2)
+
+      expect(topic_page).to have_unassigned_from_post(user: staff_user, at_post: 4)
+      expect(page).to have_no_css("#topic .assigned-to")
+    end
+
+    it "can submit form with shortcut from texatea" do
+      visit "/t/#{topic.id}"
+
+      topic_page.click_assign_post(post2)
+      assign_modal.assignee = staff_user
+
+      find("body").send_keys(:tab)
+      find("body").send_keys(:control, :enter)
+
+      expect(assign_modal).to be_closed
+      expect(topic_page).to have_assigned_post(user: staff_user, at_post: 3)
+      expect(topic_page.find_post_assign(post1.post_number)).to have_content(staff_user.username)
+      expect(topic_page.find_post_assign(post2.post_number)).to have_content(staff_user.username)
+    end
+
+    context "when prioritize_full_name_in_ux setting is enabled" do
+      before { SiteSetting.prioritize_full_name_in_ux = true }
+
+      it "shows the user's name after assign" do
+        visit "/t/#{topic.id}"
+
+        topic_page.click_assign_post(post2)
+        assign_modal.assignee = staff_user
+        assign_modal.confirm
+        expect(topic_page.find_post_assign(post1.post_number)).to have_content(staff_user.name)
+        expect(topic_page.find_post_assign(post2.post_number)).to have_content(staff_user.name)
+      end
+    end
+
+    context "when assigns are not public" do
+      before { SiteSetting.assigns_public = false }
+
+      it "assigned small action post has 'private-assign' in class attribute" do
+        visit "/t/#{topic.id}"
+
+        topic_page.click_assign_post(post2)
+        assign_modal.assignee = staff_user
+        assign_modal.confirm
+
+        expect(assign_modal).to be_closed
+        expect(topic_page).to have_assigned_post(
+          user: staff_user,
+          at_post: 3,
+          class_attribute: ".private-assign",
+        )
+      end
+    end
+
+    context "when unassign_on_close is set to true" do
+      before { SiteSetting.unassign_on_close = true }
+
+      it "unassigns the topic on close" do
+        visit "/t/#{topic.id}"
+
+        topic_page.click_assign_post(post2)
+        assign_modal.assignee = staff_user
+        assign_modal.confirm
+
+        expect(assign_modal).to be_closed
+        expect(topic_page).to have_assigned_post(user: staff_user, at_post: 3)
+
+        find(".timeline-controls .toggle-admin-menu").click
+        find(".topic-admin-close").click
+
+        expect(find("#post_4")).to have_content(
+          I18n.t("js.action_codes.closed.enabled", when: "just now"),
+        )
+        expect(page).to have_no_css("#post_5")
+        expect(page).to have_no_css("#topic .assigned-to")
+      end
+
+      it "can assign the previous assignee" do
+        visit "/t/#{topic.id}"
+
+        topic_page.click_assign_post(post2)
+        assign_modal.assignee = staff_user
+        assign_modal.confirm
+
+        expect(assign_modal).to be_closed
+        expect(topic_page).to have_assigned_post(user: staff_user, at_post: 3)
+
+        find(".timeline-controls .toggle-admin-menu").click
+        find(".topic-admin-close").click
+
+        expect(find("#post_4")).to have_content(
+          I18n.t("js.action_codes.closed.enabled", when: "just now"),
+        )
+        expect(page).to have_no_css("#post_5")
+        expect(page).to have_no_css("#topic .assigned-to")
+
+        topic_page.click_assign_post(post2)
+        assign_modal.assignee = staff_user
+        assign_modal.confirm
+
+        expect(page).to have_no_css("#post_5")
+        expect(topic_page.find_post_assign(post1.post_number)).to have_content(staff_user.username)
+        expect(topic_page.find_post_assign(post2.post_number)).to have_content(staff_user.username)
+      end
+
+      context "when reassign_on_open is set to true" do
+        before { SiteSetting.reassign_on_open = true }
+
+        it "reassigns the topic on open" do
+          visit "/t/#{topic.id}"
+
+          topic_page.click_assign_post(post2)
+          assign_modal.assignee = staff_user
+          assign_modal.confirm
+
+          expect(assign_modal).to be_closed
+          expect(topic_page).to have_assigned_post(user: staff_user, at_post: 3)
+
+          find(".timeline-controls .toggle-admin-menu").click
+          find(".topic-admin-close").click
+
+          expect(find("#post_4")).to have_content(
+            I18n.t("js.action_codes.closed.enabled", when: "just now"),
+          )
+          expect(page).to have_no_css("#post_5")
+          expect(page).to have_no_css("#topic .assigned-to")
+
+          find(".timeline-controls .toggle-admin-menu").click
+          find(".topic-admin-open").click
+
+          expect(find("#post_5")).to have_content(
+            I18n.t("js.action_codes.closed.disabled", when: "just now"),
+          )
+          expect(page).to have_no_css("#post_6")
+          expect(topic_page.find_post_assign(post1.post_number)).to have_content(
+            staff_user.username,
+          )
+          expect(topic_page.find_post_assign(post2.post_number)).to have_content(
+            staff_user.username,
+          )
+        end
+      end
+    end
+  end
+end
diff --git a/spec/system/assign_topic_spec.rb b/spec/system/assign_topic_spec.rb
index b30a5b7..364a5d6 100644
--- a/spec/system/assign_topic_spec.rb
+++ b/spec/system/assign_topic_spec.rb
@@ -49,6 +49,19 @@ describe "Assign | Assigning topics", type: :system do
       expect(find("#topic .assigned-to")).to have_content(staff_user.username)
     end
 
+    context "when prioritize_full_name_in_ux setting is enabled" do
+      before { SiteSetting.prioritize_full_name_in_ux = true }
+
+      it "shows the user's name after assign" do
+        visit "/t/#{topic.id}"
+
+        topic_page.click_assign_topic
+        assign_modal.assignee = staff_user
+        assign_modal.confirm
+        expect(find("#topic .assigned-to")).to have_content(staff_user.name)
+      end
+    end
+
     context "when assigns are not public" do
       before { SiteSetting.assigns_public = false }
 
diff --git a/spec/system/page_objects/pages/topic.rb b/spec/system/page_objects/pages/topic.rb
index fe70463..81f0a0c 100644
--- a/spec/system/page_objects/pages/topic.rb
+++ b/spec/system/page_objects/pages/topic.rb
@@ -12,28 +12,62 @@ module PageObjects
         find("[data-value='unassign']").click
       end
 
+      def click_unassign_post(post)
+        find("#topic-footer-dropdown-reassign").click
+        data_value = "unassign-from-post-#{post.id}"
+        find("[data-value=\"#{data_value}\"]").click
+      end
+
+      def click_assign_post(post)
+        find_post_action_button(post, :show_more).click
+        assign_post = within_post(post) { find(".post-action-menu__assign-post") }
+        assign_post.click
+      end
+
       def click_edit_topic_assignment
         find("#topic-footer-dropdown-reassign").click
         find("[data-value='reassign']").click
       end
 
+      def find_post_assign(post_number)
+        within("#post_#{post_number}") { find(".assigned-to") }
+      end
+
       def has_assigned?(args)
         has_assignment_action?(action: "assigned", **args)
       end
 
+      def has_assigned_post?(args)
+        has_assignment_action?(action: "assigned_to_post", **args)
+      end
+
       def has_unassigned?(args)
         has_assignment_action?(action: "unassigned", **args)
       end
 
+      def has_unassigned_from_post?(args)
+        has_assignment_action?(action: "unassigned_from_post", **args)
+      end
+
       def has_assignment_action?(args)
         assignee = args[:group]&.name || args[:user]&.username
 
         container =
           args[:at_post] ? find("#post_#{args[:at_post]}#{args[:class_attribute] || ""}") : page
 
-        container.has_content?(
-          I18n.t("js.action_codes.#{args[:action]}", who: "@#{assignee}", when: "just now"),
-        )
+        post_content =
+          I18n.t(
+            "js.action_codes.#{args[:action]}",
+            path: "",
+            who: "@#{assignee}",
+            when: "just now",
+          )
+
+        if args[:action] == "assigned_to_post" || args[:action] == "unassigned_from_post"
+          post_content.gsub!(%r{<a[^>]*>(.*?)</a>}, '\1')
+        end
+
+        container.has_content?(post_content)
       end
     end
   end