Use color from Semantics.

libraries/designsystem/src/main/kotlin/io/element/android/libraries/designsystem/theme/ColorAliases.kt

@@ -70,27 +70,9 @@ val SemanticColors.pinDigitBg
 val SemanticColors.currentUserMentionPillText
     get() = if (isLight) LightColorTokens.colorGreen1100 else DarkColorTokens.colorGreen1100
 
-val SemanticColors.currentUserMentionPillBackground
-    get() = if (isLight) {
-        // We want LightDesignTokens.colorGreenAlpha400
-        Color(0x3b07b661)
-    } else {
-        // We want DarkDesignTokens.colorGreenAlpha500
-        Color(0xff003d29)
-    }
-
 val SemanticColors.mentionPillText
     get() = textPrimary
 
-val SemanticColors.mentionPillBackground
-    get() = if (isLight) {
-        // We want LightDesignTokens.colorGray400
-        Color(0x1f052e61)
-    } else {
-        // We want DarkDesignTokens.colorGray500
-        Color(0x26f4f7fa)
-    }
-
 @OptIn(CoreColorToken::class)
 val SemanticColors.bigCheckmarkBorderColor
     get() = if (isLight) LightColorTokens.colorGray400 else DarkColorTokens.colorGray400

libraries/textcomposer/impl/src/main/kotlin/io/element/android/libraries/textcomposer/mentions/MentionSpanTheme.kt

@@ -70,9 +70,9 @@ class MentionSpanTheme(val currentUserId: UserId) {
     @Composable
     fun updateStyles() {
         currentUserTextColor = ElementTheme.colors.currentUserMentionPillText.toArgb()
-        currentUserBackgroundColor = ElementTheme.colors.currentUserMentionPillBackground.toArgb()
+        currentUserBackgroundColor = ElementTheme.colors.bgBadgeAccent.toArgb()
         otherTextColor = ElementTheme.colors.mentionPillText.toArgb()
-        otherBackgroundColor = ElementTheme.colors.mentionPillBackground.toArgb()
+        otherBackgroundColor = ElementTheme.colors.bgBadgeDefault.toArgb()
 
         typeface.value = ElementTheme.typography.fontBodyLgMedium.rememberTypeface().value
         val density = LocalDensity.current