Reproduced using latest CVS

To Reproduce

• Got to ACP->Styles->Themes
• Click edit on subsilver

Following errors shown at top of screen

[phpBB Debug] PHP Notice: in file /includes/acp/acp_styles.php on line 829: Undefined index: template_data
[phpBB Debug] PHP Notice: in file /adm/index.php on line 154: Cannot modify header information - headers already sent by (output started at /includes/functions.php:2333)
[phpBB Debug] PHP Notice: in file /adm/index.php on line 155: Cannot modify header information - headers already sent by (output started at /includes/functions.php:2333)
[phpBB Debug] PHP Notice: in file /adm/index.php on line 156: Cannot modify header information - headers already sent by (output started at /includes/functions.php:2333)

Using fresh install on latest CVS