diff --git a/src/display_buffer.cc b/src/display_buffer.cc
index dbc3a596..d9ab9609 100644
--- a/src/display_buffer.cc
+++ b/src/display_buffer.cc
@@ -1,7 +1,6 @@
 #include "display_buffer.hh"
 
 #include "assert.hh"
-#include "utf8.hh"
 
 namespace Kakoune
 {
@@ -12,8 +11,6 @@ DisplayLine::iterator DisplayLine::split(iterator it, BufferIterator pos)
     assert(it->content.begin() < pos);
     assert(it->content.end() > pos);
 
-    assert(utf8::is_character_start(pos));
-
     DisplayAtom atom = *it;
     atom.content.m_end = pos;
     it->content.m_begin = pos;