Change <a> elements to underline on hover (#17898)

Fomantic brings a opinionated style that removed underline on mouse
hover which I think is important UX to have.

This re-enables the underline in the Fomantic config and fixes a few
cases where underline was deemed disruptive.

templates/shared/issuelist.tmpl

@@ -31,14 +31,12 @@
 			</div>
 			<div class="issue-item-main f1 fc df">
 				<div class="issue-item-top-row">
-					<a class="title" href="{{if .HTMLURL}}{{.HTMLURL}}{{else}}{{$.Link}}/{{.Index}}{{end}}">
-						{{RenderEmoji .Title}}
-						{{if .IsPull }}
+					<a class="title tdn" href="{{if .HTMLURL}}{{.HTMLURL}}{{else}}{{$.Link}}/{{.Index}}{{end}}">{{RenderEmoji .Title}}</a>
+					{{if .IsPull}}
 						{{if (index $.CommitStatus .PullRequest.ID)}}
 							{{template "repo/commit_status" (index $.CommitStatus .PullRequest.ID)}}
 						{{end}}
 					{{end}}
-					</a>
 					<span class="labels-list ml-2">
 						{{range .Labels}}
 							<a class="ui label" href="{{$.Link}}?q={{$.Keyword}}&type={{$.ViewType}}&state={{$.State}}&labels={{.ID}}{{if ne $.listType "milestone"}}&milestone={{$.MilestoneID}}{{end}}&assignee={{$.AssigneeID}}" style="color: {{.ForegroundColor}}; background-color: {{.Color}}" title="{{.Description | RenderEmojiPlain}}">{{.Name | RenderEmoji}}</a>
@@ -126,14 +124,14 @@
 				</div>
 				<div class="issue-item-icon-right text grey">
 					{{range .Assignees}}
-						<a class="ui assignee tooltip" href="{{.HomeLink}}" data-content="{{.GetDisplayName}}" data-position="left center">
+						<a class="ui assignee tooltip tdn" href="{{.HomeLink}}" data-content="{{.GetDisplayName}}" data-position="left center">
 							{{avatar .}}
 						</a>
 					{{end}}
 				</div>
 				<div class="issue-item-icon-right text grey">
 					{{if .NumComments}}
-						<a href="{{if .HTMLURL}}{{.HTMLURL}}{{else}}{{$.Link}}/{{.Index}}{{end}}">
+						<a class="tdn" href="{{if .HTMLURL}}{{.HTMLURL}}{{else}}{{$.Link}}/{{.Index}}{{end}}">
 							{{svg "octicon-comment" 16 "mr-2"}}{{.NumComments}}
 						</a>
 					{{end}}

web_src/fomantic/_site/globals/site.variables

@@ -6,3 +6,4 @@
 @useCustomScrollbars: false;
 @disabledOpacity: var(--opacity-disabled);
 @variationPopupTooltip: false;
+@linkHoverUnderline: underline;

web_src/fomantic/build/semantic.css

@@ -37826,7 +37826,7 @@ a {
 
 a:hover {
   color: #1e70bf;
-  text-decoration: none;
+  text-decoration: underline;
 }
 
 /*******************************

web_src/less/_base.less

@@ -236,6 +236,7 @@ a,
 .ui.breadcrumb a {
   color: var(--color-primary);
   cursor: pointer;
+  text-decoration-skip-ink: all;
 }
 
 a.muted {
@@ -245,7 +246,19 @@ a.muted {
 a:hover,
 a.muted:hover,
 .ui.breadcrumb a:hover {
-  color: var(--color-primary-dark-2);
+  color: var(--color-primary);
+}
+
+a.label,
+.repository-menu a,
+.ui.search .results a,
+.ui .menu a,
+.issue-keyword a {
+  text-decoration: none !important;
+}
+
+.ui.breadcrumb a:hover {
+  text-decoration: underline !important;
 }
 
 .ui.breadcrumb .divider {

web_src/less/_repository.less

@@ -2837,20 +2837,6 @@ tbody.commit-list {
   }
 }
 
-.commit-summary a {
-  &:hover {
-    text-decoration: underline solid;
-  }
-
-  &.default-link {
-    text-decoration: none;
-
-    &:hover {
-      text-decoration: underline solid;
-    }
-  }
-}
-
 .commit-list .commit-status-link {
   display: inline-block;
   vertical-align: middle;
@@ -3012,13 +2998,12 @@ td.blob-excerpt {
   background-color: #fafafa;
 }
 
-.issue-keyword,
-.commit-body .issue-keyword:hover {
-  border-bottom: 1px dotted var(--color-text-light-2);
+.issue-keyword {
+  border-bottom: 1px dotted var(--color-text-light-3) !important;
 }
 
 .issue-keyword:hover {
-  border-bottom: none;
+  border-bottom: none !important;
 }
 
 .file-header {

web_src/less/helpers.less

@@ -6,6 +6,7 @@
 .ac { align-items: center !important; }
 .tc { text-align: center !important; }
 .tl { text-align: left !important; }
+.tdn { text-decoration: none !important; }
 .jc { justify-content: center !important; }
 .js { justify-content: flex-start !important; }
 .je { justify-content: flex-end !important; }