Refactor hiding-methods, remove jQuery show/hide, remove `.hide` class, remove inline style=display:none (#22950)

Close #22847

This PR:

* introduce Gitea's own `showElem` and related functions
* remove jQuery show/hide
* remove .hide class
* remove inline style=display:none 

From now on:

do not use:
* "[hidden]" attribute: it's too weak, can not be applied to an element
with "display: flex"
* ".hidden" class: it has been polluted by Fomantic UI in many cases
* inline style="display: none": it's difficult to tweak
* jQuery's show/hide/toggle: it can not show/hide elements with
"display: xxx !important"

only use:
* this ".gt-hidden" class
* showElem/hideElem/toggleElem functions in "utils/dom.js"

cc: @silverwind , this is the all-in-one PR

12 files changed, 31 insertions, 31 deletions

diff --git a/templates/repo/issue/branch_selector_field.tmpl b/templates/repo/issue/branch_selector_field.tmpl
index 0d87b0687c..51eb5e26a0 100644
--- a/templates/repo/issue/branch_selector_field.tmpl
+++ b/templates/repo/issue/branch_selector_field.tmpl
@@ -39,7 +39,7 @@
 				<div class="item" data-id="refs/heads/{{.}}" data-name="{{.}}" data-id-selector="#ref_selector">{{.}}</div>
 			{{end}}
 		</div>
-		<div id="tag-list" class="scrolling menu reference-list-menu {{if not .Issue}}new-issue{{end}}" style="display: none">
+		<div id="tag-list" class="scrolling menu reference-list-menu {{if not .Issue}}new-issue{{end}} gt-hidden">
 			{{if .Reference}}
 				<div class="item text small" data-id="" data-id-selector="#ref_selector"><strong><a href="#">{{.locale.Tr "repo.clear_ref"}}</a></strong></div>
 			{{end}}
diff --git a/templates/repo/issue/labels/label.tmpl b/templates/repo/issue/labels/label.tmpl
index 87d8f0c41c..6e9177aec2 100644
--- a/templates/repo/issue/labels/label.tmpl
+++ b/templates/repo/issue/labels/label.tmpl
@@ -1,5 +1,5 @@
 <a
-	class="item {{if not .label.IsChecked}}hide{{end}}"
+	class="item {{if not .label.IsChecked}}gt-hidden{{end}}"
 	id="label_{{.label.ID}}"
 	href="{{.root.RepoLink}}/{{if or .root.IsPull .root.Issue.IsPull}}pulls{{else}}issues{{end}}?labels={{.label.ID}}"{{/* FIXME: use .root.Issue.Link or create .root.Link */}}
 >
diff --git a/templates/repo/issue/labels/labels_sidebar.tmpl b/templates/repo/issue/labels/labels_sidebar.tmpl
index e2ef38d625..bd878d6f5c 100644
--- a/templates/repo/issue/labels/labels_sidebar.tmpl
+++ b/templates/repo/issue/labels/labels_sidebar.tmpl
@@ -1,5 +1,5 @@
 <div class="ui labels list">
-	<span class="no-select item {{if .ctx.HasSelectedLabel}}hide{{end}}">{{.ctx.locale.Tr "repo.issues.new.no_label"}}</span>
+	<span class="no-select item {{if .ctx.HasSelectedLabel}}gt-hidden{{end}}">{{.ctx.locale.Tr "repo.issues.new.no_label"}}</span>
 	<span class="labels-list">
 		{{range .ctx.Labels}}
 			{{template "repo/issue/labels/label" dict "root" $.root "label" .}}
diff --git a/templates/repo/issue/list.tmpl b/templates/repo/issue/list.tmpl
index 0e4969a706..2b1bea822f 100644
--- a/templates/repo/issue/list.tmpl
+++ b/templates/repo/issue/list.tmpl
@@ -199,7 +199,7 @@
 				</div>
 			</div>
 		</div>
-		<div id="issue-actions" class="ui stackable grid hide">
+		<div id="issue-actions" class="ui stackable grid gt-hidden">
 			<div class="six wide column">
 				{{template "repo/issue/openclose" .}}
 			</div>
diff --git a/templates/repo/issue/milestone_issues.tmpl b/templates/repo/issue/milestone_issues.tmpl
index 57012bddb6..fca9597446 100644
--- a/templates/repo/issue/milestone_issues.tmpl
+++ b/templates/repo/issue/milestone_issues.tmpl
@@ -135,7 +135,7 @@
 				</div>
 			</div>
 		</div>
-		<div id="issue-actions" class="ui stackable grid hide">
+		<div id="issue-actions" class="ui stackable grid gt-hidden">
 			<div class="six wide column">
 				{{template "repo/issue/openclose" .}}
 			</div>
diff --git a/templates/repo/issue/new_form.tmpl b/templates/repo/issue/new_form.tmpl
index 2a6fcaa995..8346d07a13 100644
--- a/templates/repo/issue/new_form.tmpl
+++ b/templates/repo/issue/new_form.tmpl
@@ -134,7 +134,7 @@
 				</div>
 			</div>
 			<div class="ui select-milestone list">
-				<span class="no-select item {{if .Milestone}}hide{{end}}">{{.locale.Tr "repo.issues.new.no_milestone"}}</span>
+				<span class="no-select item {{if .Milestone}}gt-hidden{{end}}">{{.locale.Tr "repo.issues.new.no_milestone"}}</span>
 				<div class="selected">
 					{{if .Milestone}}
 						<a class="item muted sidebar-item-link" href="{{.RepoLink}}/issues?milestone={{.Milestone.ID}}">
@@ -198,7 +198,7 @@
 				</div>
 			</div>
 			<div class="ui select-project list">
-				<span class="no-select item {{if .Project}}hide{{end}}">{{.locale.Tr "repo.issues.new.no_projects"}}</span>
+				<span class="no-select item {{if .Project}}gt-hidden{{end}}">{{.locale.Tr "repo.issues.new.no_projects"}}</span>
 				<div class="selected">
 					{{if .Project}}
 						<a class="item muted sidebar-item-link" href="{{.RepoLink}}/projects/{{.Project.ID}}">
@@ -236,11 +236,11 @@
 					</div>
 				</div>
 				<div class="ui assignees list">
-					<span class="no-select item {{if .HasSelectedLabel}}hide{{end}}">
+					<span class="no-select item {{if .HasSelectedLabel}}gt-hidden{{end}}">
 						{{.locale.Tr "repo.issues.new.no_assignees"}}
 					</span>
 					{{range .Assignees}}
-						<a class="hide item gt-p-2 muted" id="assignee_{{.ID}}" href="{{$.RepoLink}}/issues?assignee={{.ID}}">
+						<a class="item gt-p-2 muted gt-hidden" id="assignee_{{.ID}}" href="{{$.RepoLink}}/issues?assignee={{.ID}}">
 							{{avatar $.Context . 28 "gt-mr-3 gt-vm"}}{{.GetDisplayName}}
 						</a>
 					{{end}}
diff --git a/templates/repo/issue/view_content.tmpl b/templates/repo/issue/view_content.tmpl
index ab419472ed..887dd2c42d 100644
--- a/templates/repo/issue/view_content.tmpl
+++ b/templates/repo/issue/view_content.tmpl
@@ -77,8 +77,8 @@
 								<span class="no-content">{{.locale.Tr "repo.issues.no_content"}}</span>
 							{{end}}
 						</div>
-						<div id="issue-{{.Issue.ID}}-raw" class="raw-content hide">{{.Issue.Content}}</div>
-						<div class="edit-content-zone hide" data-write="issue-{{.Issue.ID}}-write" data-preview="issue-{{.Issue.ID}}-preview" data-update-url="{{$.RepoLink}}/issues/{{.Issue.Index}}/content" data-context="{{.RepoLink}}" data-attachment-url="{{$.RepoLink}}/issues/{{.Issue.Index}}/attachments" data-view-attachment-url="{{$.RepoLink}}/issues/{{.Issue.Index}}/view-attachments"></div>
+						<div id="issue-{{.Issue.ID}}-raw" class="raw-content gt-hidden">{{.Issue.Content}}</div>
+						<div class="edit-content-zone gt-hidden" data-write="issue-{{.Issue.ID}}-write" data-preview="issue-{{.Issue.ID}}-preview" data-update-url="{{$.RepoLink}}/issues/{{.Issue.Index}}/content" data-context="{{.RepoLink}}" data-attachment-url="{{$.RepoLink}}/issues/{{.Issue.Index}}/attachments" data-view-attachment-url="{{$.RepoLink}}/issues/{{.Issue.Index}}/view-attachments"></div>
 						{{if .Issue.Attachments}}
 							{{template "repo/issue/view_content/attachments" Dict "ctx" $ "Attachments" .Issue.Attachments "Content" .Issue.RenderedContent}}
 						{{end}}
@@ -194,7 +194,7 @@
 	{{template "repo/issue/view_content/sidebar" .}}
 </div>
 
-<div class="hide" id="edit-content-form">
+<div class="gt-hidden" id="edit-content-form">
 	<div class="ui comment form">
 		<div class="ui top tabular menu">
 			<a class="active write item">{{$.locale.Tr "write"}}</a>
@@ -224,7 +224,7 @@
 
 {{template "repo/issue/view_content/reference_issue_dialog" .}}
 
-<div class="hide" id="no-content">
+<div class="gt-hidden" id="no-content">
 	<span class="no-content">{{.locale.Tr "repo.issues.no_content"}}</span>
 </div>
 
diff --git a/templates/repo/issue/view_content/comments.tmpl b/templates/repo/issue/view_content/comments.tmpl
index 5bd5c8b48e..b81c3c7f03 100644
--- a/templates/repo/issue/view_content/comments.tmpl
+++ b/templates/repo/issue/view_content/comments.tmpl
@@ -77,8 +77,8 @@
 								<span class="no-content">{{$.locale.Tr "repo.issues.no_content"}}</span>
 							{{end}}
 						</div>
-						<div id="issuecomment-{{.ID}}-raw" class="raw-content hide">{{.Content}}</div>
-						<div class="edit-content-zone hide" data-write="issuecomment-{{.ID}}-write" data-preview="issuecomment-{{.ID}}-preview" data-update-url="{{$.RepoLink}}/comments/{{.ID}}" data-context="{{$.RepoLink}}" data-attachment-url="{{$.RepoLink}}/comments/{{.ID}}/attachments"></div>
+						<div id="issuecomment-{{.ID}}-raw" class="raw-content gt-hidden">{{.Content}}</div>
+						<div class="edit-content-zone gt-hidden" data-write="issuecomment-{{.ID}}-write" data-preview="issuecomment-{{.ID}}-preview" data-update-url="{{$.RepoLink}}/comments/{{.ID}}" data-context="{{$.RepoLink}}" data-attachment-url="{{$.RepoLink}}/comments/{{.ID}}/attachments"></div>
 						{{if .Attachments}}
 							{{template "repo/issue/view_content/attachments" Dict "ctx" $ "Attachments" .Attachments "Content" .RenderedContent}}
 						{{end}}
@@ -449,8 +449,8 @@
 									<span class="no-content">{{$.locale.Tr "repo.issues.no_content"}}</span>
 								{{end}}
 							</div>
-							<div id="issuecomment-{{.ID}}-raw" class="raw-content hide">{{.Content}}</div>
-							<div class="edit-content-zone hide" data-write="issuecomment-{{.ID}}-write" data-preview="issuecomment-{{.ID}}-preview" data-update-url="{{$.RepoLink}}/comments/{{.ID}}" data-context="{{$.RepoLink}}" data-attachment-url="{{$.RepoLink}}/comments/{{.ID}}/attachments"></div>
+							<div id="issuecomment-{{.ID}}-raw" class="raw-content gt-hidden">{{.Content}}</div>
+							<div class="edit-content-zone gt-hidden" data-write="issuecomment-{{.ID}}-write" data-preview="issuecomment-{{.ID}}-preview" data-update-url="{{$.RepoLink}}/comments/{{.ID}}" data-context="{{$.RepoLink}}" data-attachment-url="{{$.RepoLink}}/comments/{{.ID}}/attachments"></div>
 							{{if .Attachments}}
 								{{template "repo/issue/view_content/attachments" Dict "ctx" $ "Attachments" .Attachments "Content" .RenderedContent}}
 							{{end}}
@@ -576,8 +576,8 @@
 																<span class="no-content">{{$.locale.Tr "repo.issues.no_content"}}</span>
 															{{end}}
 															</div>
-															<div id="issuecomment-{{.ID}}-raw" class="raw-content hide">{{.Content}}</div>
-															<div class="edit-content-zone hide" data-write="issuecomment-{{.ID}}-write" data-preview="issuecomment-{{.ID}}-preview" data-update-url="{{$.RepoLink}}/comments/{{.ID}}" data-context="{{$.RepoLink}}" data-attachment-url="{{$.RepoLink}}/comments/{{.ID}}/attachments"></div>
+															<div id="issuecomment-{{.ID}}-raw" class="raw-content gt-hidden">{{.Content}}</div>
+															<div class="edit-content-zone gt-hidden" data-write="issuecomment-{{.ID}}-write" data-preview="issuecomment-{{.ID}}-preview" data-update-url="{{$.RepoLink}}/comments/{{.ID}}" data-context="{{$.RepoLink}}" data-attachment-url="{{$.RepoLink}}/comments/{{.ID}}/attachments"></div>
 														</div>
 														{{$reactions := .Reactions.GroupByType}}
 														{{if $reactions}}
diff --git a/templates/repo/issue/view_content/pull.tmpl b/templates/repo/issue/view_content/pull.tmpl
index dff6b5daaa..862d5d9a1b 100644
--- a/templates/repo/issue/view_content/pull.tmpl
+++ b/templates/repo/issue/view_content/pull.tmpl
@@ -456,7 +456,7 @@
 
 			{{if $.StillCanManualMerge}}
 				<div class="ui divider"></div>
-				<div class="ui form manually-merged-fields" style="display: none">
+				<div class="ui form manually-merged-fields gt-hidden">
 					<form action="{{.Link}}/merge" method="post">
 						{{.CsrfTokenHtml}}
 						<div class="field">
diff --git a/templates/repo/issue/view_content/pull_merge_instruction.tmpl b/templates/repo/issue/view_content/pull_merge_instruction.tmpl
index 5a7f6e867b..78deed9567 100644
--- a/templates/repo/issue/view_content/pull_merge_instruction.tmpl
+++ b/templates/repo/issue/view_content/pull_merge_instruction.tmpl
@@ -1,6 +1,6 @@
 <div class="ui divider"></div>
 <div class="instruct-toggle"> {{$.locale.Tr "repo.pulls.merge_instruction_hint" | Safe}} </div>
-<div class="instruct-content gt-mt-3" style="display:none">
+<div class="instruct-content gt-mt-3 gt-hidden">
 	<div><h3 class="gt-di">{{$.locale.Tr "step1"}} </h3>{{$.locale.Tr "repo.pulls.merge_instruction_step1_desc"}}</div>
 	<div class="ui secondary segment">
 		{{if eq $.Issue.PullRequest.Flow 0}}
diff --git a/templates/repo/issue/view_content/sidebar.tmpl b/templates/repo/issue/view_content/sidebar.tmpl
index 8cd34ede6e..2b24825b5f 100644
--- a/templates/repo/issue/view_content/sidebar.tmpl
+++ b/templates/repo/issue/view_content/sidebar.tmpl
@@ -50,7 +50,7 @@
 			</div>
 
 			<div class="ui assignees list">
-				<span class="no-select item {{if or .OriginalReviews .PullReviewers}}hide{{end}}">{{.locale.Tr "repo.issues.new.no_reviewers"}}</span>
+				<span class="no-select item {{if or .OriginalReviews .PullReviewers}}gt-hidden{{end}}">{{.locale.Tr "repo.issues.new.no_reviewers"}}</span>
 				<div class="selected">
 					{{range .PullReviewers}}
 						<div class="item gt-mb-2">
@@ -202,7 +202,7 @@
 			</div>
 		</div>
 		<div class="ui select-milestone list">
-			<span class="no-select item {{if .Issue.Milestone}}hide{{end}}">{{.locale.Tr "repo.issues.new.no_milestone"}}</span>
+			<span class="no-select item {{if .Issue.Milestone}}gt-hidden{{end}}">{{.locale.Tr "repo.issues.new.no_milestone"}}</span>
 			<div class="selected">
 				{{if .Issue.Milestone}}
 					<a class="item muted sidebar-item-link" href="{{.RepoLink}}/milestone/{{.Issue.Milestone.ID}}">
@@ -259,7 +259,7 @@
 				</div>
 			</div>
 			<div class="ui select-project list">
-				<span class="no-select item {{if .Issue.ProjectID}}hide{{end}}">{{.locale.Tr "repo.issues.new.no_projects"}}</span>
+				<span class="no-select item {{if .Issue.ProjectID}}gt-hidden{{end}}">{{.locale.Tr "repo.issues.new.no_projects"}}</span>
 				<div class="selected">
 					{{if .Issue.ProjectID}}
 						<a class="item muted sidebar-item-link" href="{{.Issue.Project.Link}}">
@@ -308,7 +308,7 @@
 			</div>
 		</div>
 		<div class="ui assignees list">
-			<span class="no-select item {{if .Issue.Assignees}}hide{{end}}">{{.locale.Tr "repo.issues.new.no_assignees"}}</span>
+			<span class="no-select item {{if .Issue.Assignees}}gt-hidden{{end}}">{{.locale.Tr "repo.issues.new.no_assignees"}}</span>
 			<div class="selected">
 				{{range .Issue.Assignees}}
 					<div class="item">
@@ -423,7 +423,7 @@
 		<div class="ui divider"></div>
 		<span class="text"><strong>{{.locale.Tr "repo.issues.due_date"}}</strong></span>
 		<div class="ui form" id="deadline-loader">
-			<div class="ui negative message" id="deadline-err-invalid-date" style="display: none;">
+			<div class="ui negative message gt-hidden" id="deadline-err-invalid-date">
 				{{svg "octicon-x" 16 "close icon"}}
 				{{.locale.Tr "repo.issues.due_date_invalid"}}
 			</div>
@@ -447,7 +447,7 @@
 			{{end}}
 
 			{{if and .HasIssuesOrPullsWritePermission (not .Repository.IsArchived)}}
-				<div {{if ne .Issue.DeadlineUnix 0}} style="display: none;"{{end}} id="deadlineForm">
+				<div {{if ne .Issue.DeadlineUnix 0}} class="gt-hidden"{{end}} id="deadlineForm">
 					<form class="ui fluid action input issue-due-form" action="{{AppSubUrl}}/{{PathEscape .Repository.Owner.Name}}/{{PathEscape .Repository.Name}}/issues/{{.Issue.Index}}/deadline" method="post" id="update-issue-deadline-form">
 						{{$.CsrfTokenHtml}}
 						<input required placeholder="{{.locale.Tr "repo.issues.due_date_form"}}" {{if gt .Issue.DeadlineUnix 0}}value="{{.Issue.DeadlineUnix.Format "2006-01-02"}}"{{end}} type="date" name="deadlineDate" id="deadlineDate">
diff --git a/templates/repo/issue/view_title.tmpl b/templates/repo/issue/view_title.tmpl
index 7ba6198b62..b43253f90b 100644
--- a/templates/repo/issue/view_title.tmpl
+++ b/templates/repo/issue/view_title.tmpl
@@ -8,14 +8,14 @@
 		<h1>
 			<span id="issue-title">{{RenderIssueTitle $.Context .Issue.Title $.RepoLink $.Repository.ComposeMetas | RenderCodeBlock}}</span>
 			<span class="index">#{{.Issue.Index}}</span>
-			<div id="edit-title-input" class="ui input gt-ml-4" style="display: none">
+			<div id="edit-title-input" class="ui input gt-ml-4 gt-hidden">
 				<input value="{{.Issue.Title}}" maxlength="255" autocomplete="off">
 			</div>
 		</h1>
 		{{if and (or .HasIssuesOrPullsWritePermission .IsIssuePoster) (not .Repository.IsArchived)}}
 			<div class="edit-buttons">
-				<button id="cancel-edit-title" class="ui basic button secondary in-edit" style="display: none">{{.locale.Tr "repo.issues.cancel"}}</button>
-				<button id="save-edit-title" class="ui primary button in-edit" style="display: none" data-update-url="{{$.RepoLink}}/issues/{{.Issue.Index}}/title" {{if .Issue.IsPull}}data-target-update-url="{{$.RepoLink}}/pull/{{.Issue.Index}}/target_branch"{{end}}>{{.locale.Tr "repo.issues.save"}}</button>
+				<button id="cancel-edit-title" class="ui basic button secondary in-edit gt-hidden">{{.locale.Tr "repo.issues.cancel"}}</button>
+				<button id="save-edit-title" class="ui primary button in-edit gt-hidden" data-update-url="{{$.RepoLink}}/issues/{{.Issue.Index}}/title" {{if .Issue.IsPull}}data-target-update-url="{{$.RepoLink}}/pull/{{.Issue.Index}}/target_branch"{{end}}>{{.locale.Tr "repo.issues.save"}}</button>
 			</div>
 		{{end}}
 	</div>
@@ -61,7 +61,7 @@
 					{{$.locale.Tr "repo.pulls.title_desc" .NumCommits $headHref $baseHref | Safe}}
 				</span>
 			{{end}}
-			<span id="pull-desc-edit" style="display: none">
+			<span id="pull-desc-edit gt-hidden">
 				<div class="ui floating filter dropdown">
 					<div class="ui basic small button">
 						<span class="text">{{.locale.Tr "repo.pulls.compare_compare"}}: {{$.HeadTarget}}</span>