From 4c4b43124862a4ee564cb8d6dafa44be8c95cb78 Mon Sep 17 00:00:00 2001
From: Leah <kevinlukej@gmail.com>
Date: Thu, 23 May 2024 18:08:31 +0000
Subject: [PATCH] Ported cutiekeys followmouse mfm

---
 locales/en-US.yml                             |   3 +
 .../frontend/src/components/CkFollowMouse.vue |  81 +++++++++++
 .../frontend/src/components/MkMfmWindow.vue   | 134 ++++++++++--------
 .../global/MkMisskeyFlavoredMarkdown.ts       |  23 +++
 packages/frontend/src/const.ts                |   5 +-
 5 files changed, 184 insertions(+), 62 deletions(-)
 create mode 100644 packages/frontend/src/components/CkFollowMouse.vue

diff --git a/locales/en-US.yml b/locales/en-US.yml
index fe27a131ba..07173c131e 100644
--- a/locales/en-US.yml
+++ b/locales/en-US.yml
@@ -2478,6 +2478,7 @@ _moderationLogTypes:
   unsetUserAvatar: "Unset this user's avatar"
   unsetUserBanner: "Unset this user's banner"
 _mfm:
+  uncommonFeature: "This is not a widespread feature, it may not display properly on most other fedi software, including other Misskey forks"
   intro: "MFM is a markup language used on Misskey, Sharkey, Firefish, Akkoma, and more that can be used in many places. Here you can view a list of all available MFM syntax."
   dummy: "Sharkey expands the world of the Fediverse"
   mention: "Mention"
@@ -2542,6 +2543,8 @@ _mfm:
   rotateDescription: "Turns content by a specified angle."
   position: "Position"
   positionDescription: "Move content by a specified amount."
+  followMouse: "Follow Mouse"
+  followMouseDescription: "Content will follow the mouse. On mobile it will follow wherever the user taps."
   scale: "Scale"
   scaleDescription: "Scale content by a specified amount."
   foreground: "Foreground color"
diff --git a/packages/frontend/src/components/CkFollowMouse.vue b/packages/frontend/src/components/CkFollowMouse.vue
new file mode 100644
index 0000000000..b55a577b3f
--- /dev/null
+++ b/packages/frontend/src/components/CkFollowMouse.vue
@@ -0,0 +1,81 @@
+<template>
+<span ref="container" :class="$style.root">
+	<span ref="el" :class="$style.inner" style="position: absolute">
+		<slot></slot>
+	</span>
+</span>
+</template>
+
+<script lang="ts" setup>
+import { onMounted, onUnmounted, shallowRef } from 'vue';
+const el = shallowRef<HTMLElement>();
+const container = shallowRef<HTMLElement>();
+const props = defineProps({
+	x: {
+		type: Boolean,
+		default: true,
+	},
+	y: {
+		type: Boolean,
+		default: true,
+	},
+	speed: {
+		type: String,
+		default: '0.1s',
+	},
+	rotateByVelocity: {
+		type: Boolean,
+		default: true,
+	},
+});
+
+let lastX = 0;
+let lastY = 0;
+let oldAngle = 0;
+
+function lerp(a, b, alpha) {
+	return a + alpha * (b - a);
+}
+
+const updatePosition = (mouseEvent: MouseEvent) => {
+	if (el.value && container.value) {
+		const containerRect = container.value.getBoundingClientRect();
+		const newX = mouseEvent.clientX - containerRect.left;
+		const newY = mouseEvent.clientY - containerRect.top;
+		let transform = `translate(calc(${props.x ? newX : 0}px - 50%), calc(${props.y ? newY : 0}px - 50%))`;
+		if (props.rotateByVelocity) {
+			const deltaX = newX - lastX;
+			const deltaY = newY - lastY;
+			const angle = lerp(
+				oldAngle,
+				Math.atan2(deltaY, deltaX) * (180 / Math.PI),
+				0.1,
+			);
+			transform += ` rotate(${angle}deg)`;
+			oldAngle = angle;
+		}
+		el.value.style.transform = transform;
+		el.value.style.transition = `transform ${props.speed}`;
+		lastX = newX;
+		lastY = newY;
+	}
+};
+
+onMounted(() => {
+	window.addEventListener('mousemove', updatePosition);
+});
+
+onUnmounted(() => {
+	window.removeEventListener('mousemove', updatePosition);
+});
+</script>
+
+<style lang="scss" module>
+.root {
+	position: relative;
+	display: inline-block;
+}
+.inner {
+	transform-origin: center center;
+}
+</style>
diff --git a/packages/frontend/src/components/MkMfmWindow.vue b/packages/frontend/src/components/MkMfmWindow.vue
index ce2a0e7391..fd23eb0097 100644
--- a/packages/frontend/src/components/MkMfmWindow.vue
+++ b/packages/frontend/src/components/MkMfmWindow.vue
@@ -9,17 +9,17 @@
 	<template #header>
 		MFM Cheatsheet
 	</template>
-    <MkStickyContainer>
+	<MkStickyContainer>
 		<MkSpacer :contentMax="800">
 			<div class="mfm-cheat-sheet">
 				<div>{{ i18n.ts._mfm.intro }}</div>
-				<br />
+				<br/>
 				<div class="section _block">
 					<div class="title">{{ i18n.ts._mfm.mention }}</div>
 					<div class="content">
 						<p>{{ i18n.ts._mfm.mentionDescription }}</p>
 						<div class="preview">
-							<Mfm :text="preview_mention" />
+							<Mfm :text="preview_mention"/>
 							<MkTextarea v-model="preview_mention"><template #label>MFM</template></MkTextarea>
 						</div>
 					</div>
@@ -29,7 +29,7 @@
 					<div class="content">
 						<p>{{ i18n.ts._mfm.hashtagDescription }}</p>
 						<div class="preview">
-							<Mfm :text="preview_hashtag" />
+							<Mfm :text="preview_hashtag"/>
 							<MkTextarea v-model="preview_hashtag"><template #label>MFM</template></MkTextarea>
 						</div>
 					</div>
@@ -39,7 +39,7 @@
 					<div class="content">
 						<p>{{ i18n.ts._mfm.linkDescription }}</p>
 						<div class="preview">
-							<Mfm :text="preview_link" />
+							<Mfm :text="preview_link"/>
 							<MkTextarea v-model="preview_link"><template #label>MFM</template></MkTextarea>
 						</div>
 					</div>
@@ -49,7 +49,7 @@
 					<div class="content">
 						<p>{{ i18n.ts._mfm.emojiDescription }}</p>
 						<div class="preview">
-							<Mfm :text="preview_emoji" />
+							<Mfm :text="preview_emoji"/>
 							<MkTextarea v-model="preview_emoji"><template #label>MFM</template></MkTextarea>
 						</div>
 					</div>
@@ -59,7 +59,7 @@
 					<div class="content">
 						<p>{{ i18n.ts._mfm.boldDescription }}</p>
 						<div class="preview">
-							<Mfm :text="preview_bold" />
+							<Mfm :text="preview_bold"/>
 							<MkTextarea v-model="preview_bold"><template #label>MFM</template></MkTextarea>
 						</div>
 					</div>
@@ -69,7 +69,7 @@
 					<div class="content">
 						<p>{{ i18n.ts._mfm.smallDescription }}</p>
 						<div class="preview">
-							<Mfm :text="preview_small" />
+							<Mfm :text="preview_small"/>
 							<MkTextarea v-model="preview_small"><template #label>MFM</template></MkTextarea>
 						</div>
 					</div>
@@ -79,7 +79,7 @@
 					<div class="content">
 						<p>{{ i18n.ts._mfm.quoteDescription }}</p>
 						<div class="preview">
-							<Mfm :text="preview_quote" />
+							<Mfm :text="preview_quote"/>
 							<MkTextarea v-model="preview_quote"><template #label>MFM</template></MkTextarea>
 						</div>
 					</div>
@@ -89,7 +89,7 @@
 					<div class="content">
 						<p>{{ i18n.ts._mfm.centerDescription }}</p>
 						<div class="preview">
-							<Mfm :text="preview_center" />
+							<Mfm :text="preview_center"/>
 							<MkTextarea v-model="preview_center"><template #label>MFM</template></MkTextarea>
 						</div>
 					</div>
@@ -99,7 +99,7 @@
 					<div class="content">
 						<p>{{ i18n.ts._mfm.inlineCodeDescription }}</p>
 						<div class="preview">
-							<Mfm :text="preview_inlineCode" />
+							<Mfm :text="preview_inlineCode"/>
 							<MkTextarea v-model="preview_inlineCode"><template #label>MFM</template></MkTextarea>
 						</div>
 					</div>
@@ -109,7 +109,7 @@
 					<div class="content">
 						<p>{{ i18n.ts._mfm.blockCodeDescription }}</p>
 						<div class="preview">
-							<Mfm :text="preview_blockCode" />
+							<Mfm :text="preview_blockCode"/>
 							<MkTextarea v-model="preview_blockCode"><template #label>MFM</template></MkTextarea>
 						</div>
 					</div>
@@ -119,7 +119,7 @@
 					<div class="content">
 						<p>{{ i18n.ts._mfm.inlineMathDescription }}</p>
 						<div class="preview">
-							<Mfm :text="preview_inlineMath" />
+							<Mfm :text="preview_inlineMath"/>
 							<MkTextarea v-model="preview_inlineMath"><template #label>MFM</template></MkTextarea>
 						</div>
 					</div>
@@ -129,7 +129,7 @@
 					<div class="content">
 						<p>{{ i18n.ts._mfm.blockMathDescription }}</p>
 						<div class="preview">
-							<Mfm :text="preview_blockMath" />
+							<Mfm :text="preview_blockMath"/>
 							<MkTextarea v-model="preview_blockMath"><template #label>MFM</template></MkTextarea>
 						</div>
 					</div>
@@ -139,7 +139,7 @@
 					<div class="content">
 						<p>{{ i18n.ts._mfm.searchDescription }}</p>
 						<div class="preview">
-							<Mfm :text="preview_search" />
+							<Mfm :text="preview_search"/>
 							<MkTextarea v-model="preview_search"><template #label>MFM</template></MkTextarea>
 						</div>
 					</div>
@@ -149,7 +149,7 @@
 					<div class="content">
 						<p>{{ i18n.ts._mfm.flipDescription }}</p>
 						<div class="preview">
-							<Mfm :text="preview_flip" />
+							<Mfm :text="preview_flip"/>
 							<MkTextarea v-model="preview_flip"><template #label>MFM</template></MkTextarea>
 						</div>
 					</div>
@@ -159,7 +159,7 @@
 					<div class="content">
 						<p>{{ i18n.ts._mfm.fontDescription }}</p>
 						<div class="preview">
-							<Mfm :text="preview_font" />
+							<Mfm :text="preview_font"/>
 							<MkTextarea v-model="preview_font"><template #label>MFM</template></MkTextarea>
 						</div>
 					</div>
@@ -169,7 +169,7 @@
 					<div class="content">
 						<p>{{ i18n.ts._mfm.x2Description }}</p>
 						<div class="preview">
-							<Mfm :text="preview_x2" />
+							<Mfm :text="preview_x2"/>
 							<MkTextarea v-model="preview_x2"><template #label>MFM</template></MkTextarea>
 						</div>
 					</div>
@@ -179,7 +179,7 @@
 					<div class="content">
 						<p>{{ i18n.ts._mfm.x3Description }}</p>
 						<div class="preview">
-							<Mfm :text="preview_x3" />
+							<Mfm :text="preview_x3"/>
 							<MkTextarea v-model="preview_x3"><template #label>MFM</template></MkTextarea>
 						</div>
 					</div>
@@ -189,7 +189,7 @@
 					<div class="content">
 						<p>{{ i18n.ts._mfm.x4Description }}</p>
 						<div class="preview">
-							<Mfm :text="preview_x4" />
+							<Mfm :text="preview_x4"/>
 							<MkTextarea v-model="preview_x4"><template #label>MFM</template></MkTextarea>
 						</div>
 					</div>
@@ -199,7 +199,7 @@
 					<div class="content">
 						<p>{{ i18n.ts._mfm.blurDescription }}</p>
 						<div class="preview">
-							<Mfm :text="preview_blur" />
+							<Mfm :text="preview_blur"/>
 							<MkTextarea v-model="preview_blur"><template #label>MFM</template></MkTextarea>
 						</div>
 					</div>
@@ -209,7 +209,7 @@
 					<div class="content">
 						<p>{{ i18n.ts._mfm.jellyDescription }}</p>
 						<div class="preview">
-							<Mfm :text="preview_jelly" />
+							<Mfm :text="preview_jelly"/>
 							<MkTextarea v-model="preview_jelly"><template #label>MFM</template></MkTextarea>
 						</div>
 					</div>
@@ -219,7 +219,7 @@
 					<div class="content">
 						<p>{{ i18n.ts._mfm.tadaDescription }}</p>
 						<div class="preview">
-							<Mfm :text="preview_tada" />
+							<Mfm :text="preview_tada"/>
 							<MkTextarea v-model="preview_tada"><template #label>MFM</template></MkTextarea>
 						</div>
 					</div>
@@ -229,7 +229,7 @@
 					<div class="content">
 						<p>{{ i18n.ts._mfm.jumpDescription }}</p>
 						<div class="preview">
-							<Mfm :text="preview_jump" />
+							<Mfm :text="preview_jump"/>
 							<MkTextarea v-model="preview_jump"><template #label>MFM</template></MkTextarea>
 						</div>
 					</div>
@@ -239,7 +239,7 @@
 					<div class="content">
 						<p>{{ i18n.ts._mfm.bounceDescription }}</p>
 						<div class="preview">
-							<Mfm :text="preview_bounce" />
+							<Mfm :text="preview_bounce"/>
 							<MkTextarea v-model="preview_bounce"><template #label>MFM</template></MkTextarea>
 						</div>
 					</div>
@@ -249,7 +249,7 @@
 					<div class="content">
 						<p>{{ i18n.ts._mfm.spinDescription }}</p>
 						<div class="preview">
-							<Mfm :text="preview_spin" />
+							<Mfm :text="preview_spin"/>
 							<MkTextarea v-model="preview_spin"><template #label>MFM</template></MkTextarea>
 						</div>
 					</div>
@@ -259,7 +259,7 @@
 					<div class="content">
 						<p>{{ i18n.ts._mfm.shakeDescription }}</p>
 						<div class="preview">
-							<Mfm :text="preview_shake" />
+							<Mfm :text="preview_shake"/>
 							<MkTextarea v-model="preview_shake"><template #label>MFM</template></MkTextarea>
 						</div>
 					</div>
@@ -269,7 +269,7 @@
 					<div class="content">
 						<p>{{ i18n.ts._mfm.twitchDescription }}</p>
 						<div class="preview">
-							<Mfm :text="preview_twitch" />
+							<Mfm :text="preview_twitch"/>
 							<MkTextarea v-model="preview_twitch"><template #label>MFM</template></MkTextarea>
 						</div>
 					</div>
@@ -279,7 +279,7 @@
 					<div class="content">
 						<p>{{ i18n.ts._mfm.rainbowDescription }}</p>
 						<div class="preview">
-							<Mfm :text="preview_rainbow" />
+							<Mfm :text="preview_rainbow"/>
 							<MkTextarea v-model="preview_rainbow"><template #label>MFM</template></MkTextarea>
 						</div>
 					</div>
@@ -289,7 +289,7 @@
 					<div class="content">
 						<p>{{ i18n.ts._mfm.sparkleDescription }}</p>
 						<div class="preview">
-							<Mfm :text="preview_sparkle" />
+							<Mfm :text="preview_sparkle"/>
 							<MkTextarea v-model="preview_sparkle"><span>MFM</span></MkTextarea>
 						</div>
 					</div>
@@ -299,7 +299,7 @@
 					<div class="content">
 						<p>{{ i18n.ts._mfm.rotateDescription }}</p>
 						<div class="preview">
-							<Mfm :text="preview_rotate" />
+							<Mfm :text="preview_rotate"/>
 							<MkTextarea v-model="preview_rotate"><span>MFM</span></MkTextarea>
 						</div>
 					</div>
@@ -309,17 +309,29 @@
 					<div class="content">
 						<p>{{ i18n.ts._mfm.positionDescription }}</p>
 						<div class="preview">
-							<Mfm :text="preview_position" />
+							<Mfm :text="preview_position"/>
 							<MkTextarea v-model="preview_position"><span>MFM</span></MkTextarea>
 						</div>
 					</div>
 				</div>
+				<div class="section _block" style="overflow: hidden">
+					<div class="title">{{ i18n.ts._mfm.followMouse }}</div>
+					<MkInfo warn>{{  i18n.ts._mfm.uncommonFeature }}</MkInfo>
+					<br/>
+					<div class="content">
+						<p>{{ i18n.ts._mfm.followMouseDescription }}</p>
+						<div class="preview">
+							<Mfm :text="preview_followmouse"/>
+							<MkTextarea v-model="preview_followmouse"><span>MFM</span></MkTextarea>
+						</div>
+					</div>
+				</div>
 				<div class="section _block">
 					<div class="title">{{ i18n.ts._mfm.scale }}</div>
 					<div class="content">
 						<p>{{ i18n.ts._mfm.scaleDescription }}</p>
 						<div class="preview">
-							<Mfm :text="preview_scale" />
+							<Mfm :text="preview_scale"/>
 							<MkTextarea v-model="preview_scale"><span>MFM</span></MkTextarea>
 						</div>
 					</div>
@@ -329,7 +341,7 @@
 					<div class="content">
 						<p>{{ i18n.ts._mfm.foregroundDescription }}</p>
 						<div class="preview">
-							<Mfm :text="preview_fg" />
+							<Mfm :text="preview_fg"/>
 							<MkTextarea v-model="preview_fg"><span>MFM</span></MkTextarea>
 						</div>
 					</div>
@@ -339,7 +351,7 @@
 					<div class="content">
 						<p>{{ i18n.ts._mfm.backgroundDescription }}</p>
 						<div class="preview">
-							<Mfm :text="preview_bg" />
+							<Mfm :text="preview_bg"/>
 							<MkTextarea v-model="preview_bg"><span>MFM</span></MkTextarea>
 						</div>
 					</div>
@@ -349,7 +361,7 @@
 					<div class="content">
 						<p>{{ i18n.ts._mfm.plainDescription }}</p>
 						<div class="preview">
-							<Mfm :text="preview_plain" />
+							<Mfm :text="preview_plain"/>
 							<MkTextarea v-model="preview_plain"><span>MFM</span></MkTextarea>
 						</div>
 					</div>
@@ -362,18 +374,19 @@
 
 <script lang="ts" setup>
 import { ref } from 'vue';
+import MkInfo from './MkInfo.vue';
 import MkWindow from '@/components/MkWindow.vue';
 import MkTextarea from '@/components/MkTextarea.vue';
-import { i18n } from "@/i18n.js";
+import { i18n } from '@/i18n.js';
 
 const emit = defineEmits<{
 	(ev: 'closed'): void;
 }>();
 
-const preview_mention = ref("@example");
-const preview_hashtag = ref("#test");
+const preview_mention = ref('@example');
+const preview_hashtag = ref('#test');
 const preview_link = ref(`[${i18n.ts._mfm.dummy}](https://joinsharkey.org)`);
-const preview_emoji = ref(`:heart:`);
+const preview_emoji = ref(':heart:');
 const preview_bold = ref(`**${i18n.ts._mfm.dummy}**`);
 const preview_small = ref(
 	`<small>${i18n.ts._mfm.dummy}</small>`,
@@ -386,33 +399,33 @@ const preview_blockCode = ref(
 	'```\n~ (#i, 100) {\n\t<: ? ((i % 15) = 0) "FizzBuzz"\n\t\t.? ((i % 3) = 0) "Fizz"\n\t\t.? ((i % 5) = 0) "Buzz"\n\t\t. i\n}\n```',
 );
 const preview_inlineMath = ref(
-	"\\(x= \\frac{-b' \\pm \\sqrt{(b')^2-ac}}{a}\\)",
+	'\\(x= \\frac{-b\' \\pm \\sqrt{(b\')^2-ac}}{a}\\)',
 );
-const preview_blockMath = ref("\\[x= \\frac{-b' \\pm \\sqrt{(b')^2-ac}}{a}\\]");
+const preview_blockMath = ref('\\[x= \\frac{-b\' \\pm \\sqrt{(b\')^2-ac}}{a}\\]');
 const preview_quote = ref(`> ${i18n.ts._mfm.dummy}`);
 const preview_search = ref(
 	`${i18n.ts._mfm.dummy} [search]\n${i18n.ts._mfm.dummy} [検索]`,
 );
 const preview_jelly = ref(
-	"$[jelly 🍮] $[jelly.speed=3s 🍮] $[jelly.delay=3s 🍮] $[jelly.loop=3 🍮]",
+	'$[jelly 🍮] $[jelly.speed=3s 🍮] $[jelly.delay=3s 🍮] $[jelly.loop=3 🍮]',
 );
 const preview_tada = ref(
-	"$[tada 🍮] $[tada.speed=3s 🍮] $[tada.delay=3s 🍮] $[tada.loop=3 🍮]",
+	'$[tada 🍮] $[tada.speed=3s 🍮] $[tada.delay=3s 🍮] $[tada.loop=3 🍮]',
 );
 const preview_jump = ref(
-	"$[jump 🍮] $[jump.speed=3s 🍮] $[jump.delay=3s 🍮] $[jump.loop=3 🍮]",
+	'$[jump 🍮] $[jump.speed=3s 🍮] $[jump.delay=3s 🍮] $[jump.loop=3 🍮]',
 );
 const preview_bounce = ref(
-	"$[bounce 🍮] $[bounce.speed=3s 🍮] $[bounce.delay=3s 🍮] $[bounce.loop=3 🍮]",
+	'$[bounce 🍮] $[bounce.speed=3s 🍮] $[bounce.delay=3s 🍮] $[bounce.loop=3 🍮]',
 );
 const preview_shake = ref(
-	"$[shake 🍮] $[shake.speed=3s 🍮] $[shake.delay=3s 🍮] $[shake.loop=3 🍮]",
+	'$[shake 🍮] $[shake.speed=3s 🍮] $[shake.delay=3s 🍮] $[shake.loop=3 🍮]',
 );
 const preview_twitch = ref(
-	"$[twitch 🍮] $[twitch.speed=3s 🍮] $[twitch.delay=3s 🍮] $[twitch.loop=3 🍮]",
+	'$[twitch 🍮] $[twitch.speed=3s 🍮] $[twitch.delay=3s 🍮] $[twitch.loop=3 🍮]',
 );
 const preview_spin = ref(
-	"$[spin 🍮] $[spin.left 🍮] $[spin.alternate 🍮]\n$[spin.x 🍮] $[spin.x,left 🍮] $[spin.x,alternate 🍮]\n$[spin.y 🍮] $[spin.y,left 🍮] $[spin.y,alternate 🍮]\n\n$[spin.speed=3s 🍮] $[spin.delay=3s 🍮] $[spin.loop=3 🍮]",
+	'$[spin 🍮] $[spin.left 🍮] $[spin.alternate 🍮]\n$[spin.x 🍮] $[spin.x,left 🍮] $[spin.x,alternate 🍮]\n$[spin.y 🍮] $[spin.y,left 🍮] $[spin.y,alternate 🍮]\n\n$[spin.speed=3s 🍮] $[spin.delay=3s 🍮] $[spin.loop=3 🍮]',
 );
 const preview_flip = ref(
 	`$[flip ${i18n.ts._mfm.dummy}]\n$[flip.v ${i18n.ts._mfm.dummy}]\n$[flip.h,v ${i18n.ts._mfm.dummy}]`,
@@ -420,25 +433,26 @@ const preview_flip = ref(
 const preview_font = ref(
 	`$[font.serif ${i18n.ts._mfm.dummy}]\n$[font.monospace ${i18n.ts._mfm.dummy}]`,
 );
-const preview_x2 = ref("$[x2 🍮]");
-const preview_x3 = ref("$[x3 🍮]");
-const preview_x4 = ref("$[x4 🍮]");
+const preview_x2 = ref('$[x2 🍮]');
+const preview_x3 = ref('$[x3 🍮]');
+const preview_x4 = ref('$[x4 🍮]');
 const preview_blur = ref(`$[blur ${i18n.ts._mfm.dummy}]`);
 const preview_rainbow = ref(
-	"$[rainbow 🍮] $[rainbow.speed=3s 🍮] $[rainbow.delay=3s 🍮] $[rainbow.loop=3 🍮]",
+	'$[rainbow 🍮] $[rainbow.speed=3s 🍮] $[rainbow.delay=3s 🍮] $[rainbow.loop=3 🍮]',
 );
-const preview_sparkle = ref("$[sparkle 🍮]");
+const preview_sparkle = ref('$[sparkle 🍮]');
 const preview_rotate = ref(
-	"$[rotate 🍮]\n$[rotate.deg=45 🍮]\n$[rotate.x,deg=45 Hello, world!]",
+	'$[rotate 🍮]\n$[rotate.deg=45 🍮]\n$[rotate.x,deg=45 Hello, world!]',
 );
-const preview_position = ref("$[position.y=-1 🍮]\n$[position.x=-1 🍮]");
+const preview_position = ref('$[position.y=-1 🍮]\n$[position.x=-1 🍮]');
+const preview_followmouse = ref('$[followmouse.x 🍮]\n$[followmouse.x,y,rotateByVelocity,speed=0.4 🍮]');
 const preview_scale = ref(
-	"$[scale.x=1.3 🍮]\n$[scale.x=1.5,y=3 🍮]\n$[scale.y=0.3 🍮]",
+	'$[scale.x=1.3 🍮]\n$[scale.x=1.5,y=3 🍮]\n$[scale.y=0.3 🍮]',
 );
-const preview_fg = ref("$[fg.color=eb6f92 Text color]");
-const preview_bg = ref("$[bg.color=31748f Background color]");
+const preview_fg = ref('$[fg.color=eb6f92 Text color]');
+const preview_bg = ref('$[bg.color=31748f Background color]');
 const preview_plain = ref(
-	"<plain>**bold** @mention #hashtag `code` $[x2 🍮]</plain>",
+	'<plain>**bold** @mention #hashtag `code` $[x2 🍮]</plain>',
 );
 </script>
 
diff --git a/packages/frontend/src/components/global/MkMisskeyFlavoredMarkdown.ts b/packages/frontend/src/components/global/MkMisskeyFlavoredMarkdown.ts
index f8b5fcfedc..2f699ccd84 100644
--- a/packages/frontend/src/components/global/MkMisskeyFlavoredMarkdown.ts
+++ b/packages/frontend/src/components/global/MkMisskeyFlavoredMarkdown.ts
@@ -6,6 +6,7 @@
 import { VNode, h, defineAsyncComponent, SetupContext } from 'vue';
 import * as mfm from '@transfem-org/sfm-js';
 import * as Misskey from 'misskey-js';
+import CkFollowMouse from '../CkFollowMouse.vue';
 import MkUrl from '@/components/global/MkUrl.vue';
 import MkTime from '@/components/global/MkTime.vue';
 import MkLink from '@/components/MkLink.vue';
@@ -232,6 +233,28 @@ export default function (props: MfmProps, { emit }: { emit: SetupContext<MfmEven
 						style = `transform: rotate(${degrees}deg); transform-origin: center center;`;
 						break;
 					}
+					case 'followmouse': {
+						// Make sure advanced MFM is on and that reduced motion is off
+						if (!useAnim) {
+							style = '';
+							break;
+						}
+
+						let x = (!!token.props.args.x);
+						let y = (!!token.props.args.y);
+
+						if (!x && !y) {
+							x = true;
+							y = true;
+						}
+
+						return h(CkFollowMouse, {
+							x: x,
+							y: y,
+							speed: validTime(token.props.args.speed) ?? '0.1s',
+							rotateByVelocity: !!token.props.args.rotateByVelocity,
+						}, genEl(token.children, scale));
+					}
 					case 'position': {
 						if (!defaultStore.state.advancedMfm) break;
 						const x = safeParseFloat(token.props.args.x) ?? 0;
diff --git a/packages/frontend/src/const.ts b/packages/frontend/src/const.ts
index ad798067b3..4c7df613a5 100644
--- a/packages/frontend/src/const.ts
+++ b/packages/frontend/src/const.ts
@@ -162,7 +162,7 @@ export const DEFAULT_SERVER_ERROR_IMAGE_URL = 'https://launcher.moe/error.png';
 export const DEFAULT_NOT_FOUND_IMAGE_URL = 'https://launcher.moe/missingpage.webp';
 export const DEFAULT_INFO_IMAGE_URL = 'https://launcher.moe/nothinghere.png';
 
-export const MFM_TAGS = ['tada', 'jelly', 'twitch', 'shake', 'spin', 'jump', 'bounce', 'flip', 'x2', 'x3', 'x4', 'scale', 'position', 'fg', 'bg', 'border', 'font', 'blur', 'rainbow', 'sparkle', 'rotate', 'ruby', 'unixtime'];
+export const MFM_TAGS = ['tada', 'jelly', 'twitch', 'shake', 'spin', 'jump', 'bounce', 'flip', 'x2', 'x3', 'x4', 'scale', 'position', 'fg', 'bg', 'border', 'font', 'blur', 'rainbow', 'sparkle', 'rotate', 'ruby', 'unixtime', 'followmouse'];
 export const MFM_PARAMS: Record<typeof MFM_TAGS[number], string[]> = {
 	tada: ['speed=', 'delay='],
 	jelly: ['speed=', 'delay='],
@@ -179,11 +179,12 @@ export const MFM_PARAMS: Record<typeof MFM_TAGS[number], string[]> = {
 	position: ['x=', 'y='],
 	fg: ['color='],
 	bg: ['color='],
-  border: ['width=', 'style=', 'color=', 'radius=', 'noclip'],
+	border: ['width=', 'style=', 'color=', 'radius=', 'noclip'],
 	font: ['serif', 'monospace', 'cursive', 'fantasy', 'emoji', 'math'],
 	blur: [],
 	rainbow: ['speed=', 'delay='],
 	rotate: ['deg='],
 	ruby: [],
 	unixtime: [],
+	followmouse: ['x', 'y', 'rotateByVelocity', 'speed='],
 };