Change Details

**List of steps to reproduce** (step by step, including full links if applicable): Start a blank page :- Enter the following code extrcat ``` <score> \header { tagline = ##f title = \markup { "A Mighty Fortress is Our God" " " "121" } subsubtitle = "(EIN' FESTE BURG. 8,7,8,7,6,6,6,6,7)" composer = "Martin Luther, 1529" poet = \markup { \center-column { "Martin Luther, 1529" "Translated by Frederick H. Hedge, 1853" } } } </score> ``` Preview the example. **What happens?**: Example code will fail to render , generating a "unknown escaped string: `\center-column' " error. **What should have happened instead?**: The example should have generated a visible header with the relevant composer field formatted with a center column. **Software version (if not a Wikimedia wiki), browser information, screenshots, other information, etc**: Windows 7, Firefox 93.0a1 (2021-08-20)

**List of steps to reproduce** (step by step, including full links if applicable): Start a blank page :- Enter the following code extract ``` <score> \header { tagline = ##f title = \markup { "A Mighty Fortress is Our God" " " "121" } subsubtitle = "(EIN' FESTE BURG. 8,7,8,7,6,6,6,6,7)" composer = "Martin Luther, 1529" poet = \markup { \center-column { "Martin Luther, 1529" "Translated by Frederick H. Hedge, 1853" } } } </score> ``` Preview the example. **What happens?**: Example code will fail to render , generating a "unknown escaped string: `\center-column' " error. **What should have happened instead?**: The example should have generated a visible header with the relevant composer field formatted with a centered column. **Software version (if not a Wikimedia wiki), browser information, screenshots, other information, etc**: Windows 7, Firefox 93.0a1 (2021-08-20)

**List of steps to reproduce** (step by step, including full links if applicable): Start a blank page :- Enter the following code extrcatact ``` <score> \header { tagline = ##f title = \markup { "A Mighty Fortress is Our God" " " "121" } subsubtitle = "(EIN' FESTE BURG. 8,7,8,7,6,6,6,6,7)" composer = "Martin Luther, 1529" poet = \markup { \center-column { "Martin Luther, 1529" "Translated by Frederick H. Hedge, 1853" } } } </score> ``` Preview the example. **What happens?**: Example code will fail to render , generating a "unknown escaped string: `\center-column' " error. **What should have happened instead?**: The example should have generated a visible header with the relevant composer field formatted with a centered column. **Software version (if not a Wikimedia wiki), browser information, screenshots, other information, etc**: Windows 7, Firefox 93.0a1 (2021-08-20)