diff --git a/app/components/elements/ReplyEditor.jsx b/app/components/elements/ReplyEditor.jsx
index f4733c3976682c4d3ff419b193dc44652ea6a055..5b3abfbef8f64fa27d5f54c283b8cc6da047410e 100644
--- a/app/components/elements/ReplyEditor.jsx
+++ b/app/components/elements/ReplyEditor.jsx
@@ -449,7 +449,7 @@ export default formId => reduxForm(
 
             if (!linkProps) throw new Error('Unknown type: ' + type)
 
-            const formCategories = Set(category ? category.replace(/#/g,"").split(/ +/) : [])
+            const formCategories = Set(category ? category.trim().replace(/#/g,"").split(/ +/) : [])
             const rootCategory = originalPost && originalPost.category ?
                 originalPost.category : formCategories.first()
             const rootTag = /^[-a-z\d]+$/.test(rootCategory) ? rootCategory : null