diff --git a/nicegui/html.py b/nicegui/html.py
index a51bc2afa..56527c83a 100644
--- a/nicegui/html.py
+++ b/nicegui/html.py
@@ -52,6 +52,7 @@ def __init__(self, inner_html: Optional[str] = None, **kwargs) -> None:
 footer = _create_html_element('footer')
 form = _create_html_element('form')
 h1 = _create_html_element('h1')
+header = _create_html_element('header')
 hgroup = _create_html_element('hgroup')
 hr = _create_html_element('hr')
 i = _create_html_element('i')
@@ -105,6 +106,7 @@ def __init__(self, inner_html: Optional[str] = None, **kwargs) -> None:
 th = _create_html_element('th')
 thead = _create_html_element('thead')
 time = _create_html_element('time')
+tr = _create_html_element('tr')
 track = _create_html_element('track')
 u = _create_html_element('u')
 ul = _create_html_element('ul')