diff --git a/src/components/markdown-renderer/markdown-extension/legacy-short-codes/replace-legacy-speakerdeck-short-code.ts b/src/components/markdown-renderer/markdown-extension/legacy-short-codes/replace-legacy-speakerdeck-short-code.ts
index 9e8a2da17..d0d433e48 100644
--- a/src/components/markdown-renderer/markdown-extension/legacy-short-codes/replace-legacy-speakerdeck-short-code.ts
+++ b/src/components/markdown-renderer/markdown-extension/legacy-short-codes/replace-legacy-speakerdeck-short-code.ts
@@ -8,7 +8,7 @@ import markdownItRegex from 'markdown-it-regex'
 import type MarkdownIt from 'markdown-it/lib'
 import type { RegexOptions } from '../../../../external-types/markdown-it-regex/interface'
 
-export const legacySpeakerdeckRegex = /^{%speakerdeck (\w+\/[\w-]+) ?%}$/
+export const legacySpeakerdeckRegex = /^{%speakerdeck\s+(\w+\/[\w-]+)\s*%}$/
 
 /**
  * Configure the given {@link MarkdownIt} to render legacy hedgedoc 1 speakerdeck shortcodes as HTML links.