diff --git a/modules/templates/util_avatar.go b/modules/templates/util_avatar.go
index afc1091516..a468361101 100644
--- a/modules/templates/util_avatar.go
+++ b/modules/templates/util_avatar.go
@@ -34,7 +34,7 @@ func AvatarHTML(src string, size int, class, name string) template.HTML {
 		name = "avatar"
 	}
 
-	return template.HTML(`<img loading="lazy" class="` + class + `" src="` + src + `" title="` + html.EscapeString(name) + `" width="` + sizeStr + `" height="` + sizeStr + `"/>`)
+	return template.HTML(`<img loading="lazy" alt="" class="` + class + `" src="` + src + `" title="` + html.EscapeString(name) + `" width="` + sizeStr + `" height="` + sizeStr + `"/>`)
 }
 
 // Avatar renders user avatars. args: user, size (int), class (string)
diff --git a/routers/api/v1/misc/markup_test.go b/routers/api/v1/misc/markup_test.go
index df70ee49ef..32568b805f 100644
--- a/routers/api/v1/misc/markup_test.go
+++ b/routers/api/v1/misc/markup_test.go
@@ -112,7 +112,7 @@ Here are some links to the most important topics. You can find the full list of
 <h2 id="user-content-quick-links">Quick Links</h2>
 <p>Here are some links to the most important topics. You can find the full list of pages at the sidebar.</p>
 <p><a href="` + FullURL + `wiki/Configuration" rel="nofollow">Configuration</a>
-<a href="` + FullURL + `wiki/raw/images/icon-bug.png" rel="nofollow"><img src="` + FullURL + `wiki/raw/images/icon-bug.png" title="icon-bug.png" alt="images/icon-bug.png"/></a></p>
+<a href="` + FullURL + `wiki/raw/images/icon-bug.png" rel="nofollow"><img src="` + FullURL + `wiki/raw/images/icon-bug.png" title="icon-bug.png" alt=""/></a></p>
 `,
 	}
 
diff --git a/templates/install.tmpl b/templates/install.tmpl
index ae800df130..7a9b40826f 100644
--- a/templates/install.tmpl
+++ b/templates/install.tmpl
@@ -363,5 +363,5 @@
 		</div>
 	</div>
 </div>
-<img class="tw-hidden" src="{{AssetUrlPrefix}}/img/forgejo-loading.svg" width="256" height="256">
+<img class="tw-hidden" src="{{AssetUrlPrefix}}/img/forgejo-loading.svg" alt="{{ctx.Locale.Tr "loading"}}" width="256" height="256">
 {{template "base/footer" .}}
diff --git a/templates/repo/diff/image_diff.tmpl b/templates/repo/diff/image_diff.tmpl
index 0612854609..a793f54da1 100644
--- a/templates/repo/diff/image_diff.tmpl
+++ b/templates/repo/diff/image_diff.tmpl
@@ -22,7 +22,7 @@
 						{{if .blobBase}}
 						<span class="side">
 							<p class="side-header">{{ctx.Locale.Tr "repo.diff.file_before"}}</p>
-							<span class="before-container"><img class="image-before"></span>
+							<span class="before-container"><img class="image-before" alt=""></span>
 							<p>
 								<span class="bounds-info-before">
 									{{ctx.Locale.Tr "repo.diff.file_image_width"}}: <span class="text bounds-info-width"></span>
@@ -37,7 +37,7 @@
 						{{if .blobHead}}
 						<span class="side">
 							<p class="side-header">{{ctx.Locale.Tr "repo.diff.file_after"}}</p>
-							<span class="after-container"><img class="image-after"></span>
+							<span class="after-container"><img class="image-after" alt=""></span>
 							<p>
 								<span class="bounds-info-after">
 									{{ctx.Locale.Tr "repo.diff.file_image_width"}}: <span class="text bounds-info-width"></span>
@@ -55,9 +55,9 @@
 				<div class="ui bottom attached tab image-diff-container" data-tab="diff-swipe-{{.file.Index}}">
 					<div class="diff-swipe">
 						<div class="swipe-frame">
-							<span class="before-container"><img class="image-before"></span>
+							<span class="before-container"><img class="image-before" alt="{{ctx.Locale.Tr "repo.diff.file_before"}}"></span>
 							<span class="swipe-container">
-								<span class="after-container"><img class="image-after"></span>
+								<span class="after-container"><img class="image-after" alt="{{ctx.Locale.Tr "repo.diff.file_after"}}"></span>
 							</span>
 							<span class="swipe-bar">
 								<span class="handle top-handle"></span>
@@ -70,8 +70,8 @@
 					<div class="diff-overlay">
 						<input type="range" min="0" max="100" value="50">
 						<div class="overlay-frame">
-							<span class="before-container"><img class="image-before"></span>
-							<span class="after-container"><img class="image-after"></span>
+							<span class="before-container"><img class="image-before" alt="{{ctx.Locale.Tr "repo.diff.file_before"}}"></span>
+							<span class="after-container"><img class="image-after" alt="{{ctx.Locale.Tr "repo.diff.file_after"}}"></span>
 						</div>
 					</div>
 				</div>
diff --git a/templates/repo/issue/view_content/comments.tmpl b/templates/repo/issue/view_content/comments.tmpl
index c8eabb9345..604efed737 100644
--- a/templates/repo/issue/view_content/comments.tmpl
+++ b/templates/repo/issue/view_content/comments.tmpl
@@ -602,7 +602,7 @@
 			<div class="timeline-item-group">
 				<div class="timeline-item event" id="{{.HashTag}}">
 					<a class="timeline-avatar"{{if gt .Poster.ID 0}} href="{{.Poster.HomeLink}}"{{end}}>
-						<img src="{{.Poster.AvatarLink $.Context}}" width="40" height="40">
+						<img src="{{.Poster.AvatarLink $.Context}}" alt="" width="40" height="40">
 					</a>
 					<span class="badge grey">{{svg "octicon-x" 16}}</span>
 					<span class="text grey muted-links">
diff --git a/templates/repo/migrate/migrating.tmpl b/templates/repo/migrate/migrating.tmpl
index 0b53636160..3a6bb25879 100644
--- a/templates/repo/migrate/migrating.tmpl
+++ b/templates/repo/migrate/migrating.tmpl
@@ -9,7 +9,7 @@
 					<div class="ui stackable middle very relaxed page grid">
 						<div id="repo_migrating" class="sixteen wide center aligned centered column" data-migrating-task-id="{{.MigrateTask.ID}}">
 							<div>
-								<img src="{{AssetUrlPrefix}}/img/forgejo-loading.svg" width="256" height="256">
+								<img src="{{AssetUrlPrefix}}/img/forgejo-loading.svg" alt="{{ctx.Locale.Tr "loading"}}" width="256" height="256">
 							</div>
 						</div>
 						<div id="repo_migrating_failed_image" class="sixteen wide center aligned centered column tw-hidden">
diff --git a/templates/repo/settings/lfs_file.tmpl b/templates/repo/settings/lfs_file.tmpl
index 5bcd2af5bf..941d09f3e6 100644
--- a/templates/repo/settings/lfs_file.tmpl
+++ b/templates/repo/settings/lfs_file.tmpl
@@ -21,7 +21,7 @@
 					{{else if not .IsTextFile}}
 						<div class="view-raw">
 							{{if .IsImageFile}}
-								<img src="{{$.RawFileLink}}">
+								<img src="{{$.RawFileLink}}" alt="">
 							{{else if .IsVideoFile}}
 								<video controls src="{{$.RawFileLink}}">
 									<strong>{{ctx.Locale.Tr "repo.video_not_supported_in_browser"}}</strong>
diff --git a/templates/shared/webhook/icon.tmpl b/templates/shared/webhook/icon.tmpl
index 3c84f117ea..f8911fa69e 100644
--- a/templates/shared/webhook/icon.tmpl
+++ b/templates/shared/webhook/icon.tmpl
@@ -3,27 +3,27 @@
 	{{$size = .Size}}
 {{end}}
 {{if eq .HookType "forgejo"}}
-	<img width="{{$size}}" height="{{$size}}" src="{{AssetUrlPrefix}}/img/forgejo.svg">
+	<img width="{{$size}}" height="{{$size}}" src="{{AssetUrlPrefix}}/img/forgejo.svg" alt="">
 {{else if eq .HookType "gitea"}}
 	{{svg "gitea-gitea" $size "img"}}
 {{else if eq .HookType "gogs"}}
-	<img width="{{$size}}" height="{{$size}}" src="{{AssetUrlPrefix}}/img/gogs.ico">
+	<img width="{{$size}}" height="{{$size}}" src="{{AssetUrlPrefix}}/img/gogs.ico" alt="">
 {{else if eq .HookType "slack"}}
-	<img width="{{$size}}" height="{{$size}}" src="{{AssetUrlPrefix}}/img/slack.png">
+	<img width="{{$size}}" height="{{$size}}" src="{{AssetUrlPrefix}}/img/slack.png" alt="">
 {{else if eq .HookType "discord"}}
-	<img width="{{$size}}" height="{{$size}}" src="{{AssetUrlPrefix}}/img/discord.png">
+	<img width="{{$size}}" height="{{$size}}" src="{{AssetUrlPrefix}}/img/discord.png" alt="">
 {{else if eq .HookType "dingtalk"}}
-	<img width="{{$size}}" height="{{$size}}" src="{{AssetUrlPrefix}}/img/dingtalk.ico">
+	<img width="{{$size}}" height="{{$size}}" src="{{AssetUrlPrefix}}/img/dingtalk.ico" alt="">
 {{else if eq .HookType "telegram"}}
-	<img width="{{$size}}" height="{{$size}}" src="{{AssetUrlPrefix}}/img/telegram.png">
+	<img width="{{$size}}" height="{{$size}}" src="{{AssetUrlPrefix}}/img/telegram.png" alt="">
 {{else if eq .HookType "msteams"}}
-	<img width="{{$size}}" height="{{$size}}" src="{{AssetUrlPrefix}}/img/msteams.png">
+	<img width="{{$size}}" height="{{$size}}" src="{{AssetUrlPrefix}}/img/msteams.png" alt="">
 {{else if eq .HookType "feishu"}}
-	<img width="{{$size}}" height="{{$size}}" src="{{AssetUrlPrefix}}/img/feishu.png">
+	<img width="{{$size}}" height="{{$size}}" src="{{AssetUrlPrefix}}/img/feishu.png" alt="">
 {{else if eq .HookType "matrix"}}
 	{{svg "gitea-matrix" $size "img"}}
 {{else if eq .HookType "wechatwork"}}
-	<img width="{{$size}}" height="{{$size}}" src="{{AssetUrlPrefix}}/img/wechatwork.png">
+	<img width="{{$size}}" height="{{$size}}" src="{{AssetUrlPrefix}}/img/wechatwork.png" alt="">
 {{else if eq .HookType "packagist"}}
-	<img width="{{$size}}" height="{{$size}}" src="{{AssetUrlPrefix}}/img/packagist.png">
+	<img width="{{$size}}" height="{{$size}}" src="{{AssetUrlPrefix}}/img/packagist.png" alt="">
 {{end}}
diff --git a/templates/user/auth/captcha.tmpl b/templates/user/auth/captcha.tmpl
index 03e360703b..9d0d6cfb6f 100644
--- a/templates/user/auth/captcha.tmpl
+++ b/templates/user/auth/captcha.tmpl
@@ -1,7 +1,7 @@
 {{if .EnableCaptcha}}{{if eq .CaptchaType "image"}}
 	<div class="inline field tw-text-center">
 		<input type="hidden" name="img-captcha-id" value="{{.Captcha}}">
-		<img style="transform: scaleX(-1)" onclick="this.src=`{{AppSubUrl}}/captcha/{{.Captcha}}.png?reload=${Date.now()}`" class="captcha-img" src="{{AppSubUrl}}/captcha/{{.Captcha}}.png">
+		<img style="transform: scaleX(-1)" onclick="this.src=`{{AppSubUrl}}/captcha/{{.Captcha}}.png?reload=${Date.now()}`" class="captcha-img" src="{{AppSubUrl}}/captcha/{{.Captcha}}.png" alt="{{ctx.Locale.Tr "captcha"}}">
 	</div>
 	<div class="required field {{if .Err_Captcha}}error{{end}}">
 		<label for="captcha">{{ctx.Locale.Tr "captcha"}}</label>
diff --git a/templates/user/dashboard/feeds.tmpl b/templates/user/dashboard/feeds.tmpl
index 85ae7266d9..8ae50bf385 100644
--- a/templates/user/dashboard/feeds.tmpl
+++ b/templates/user/dashboard/feeds.tmpl
@@ -91,7 +91,7 @@
 						{{range $push.Commits}}
 							{{$commitLink := printf "%s/commit/%s" $repoLink .Sha1}}
 							<div class="flex-text-block">
-								<img class="ui avatar" src="{{$push.AvatarLink $.Context .AuthorEmail}}" title="{{.AuthorName}}" width="16" height="16">
+								<img class="ui avatar" src="{{$push.AvatarLink $.Context .AuthorEmail}}" alt="" title="{{.AuthorName}}" width="16" height="16">
 								<a class="ui sha label" href="{{$commitLink}}">{{ShortSha .Sha1}}</a>
 								<span class="text truncate">
 									{{RenderCommitMessage $.Context .Message ($repo.ComposeMetas ctx)}}