D.S. al Coda

To coda is a normal way to tell the musician to go to the coda sign. Replacing the word coda with the sign is not unusual. Remove the coda sign you put in the to coda measure. Next, double click the coda that is in the correct measure and use shift+arrow to select the coda and copy it with ctrl+c. Next double click the words "to Coda" and replace the word Coda with the symbol using ctrl+v.

The words and symbols must be placed in the correct order from the Jumps and Repeats palette. Once they are placed they can be edited to any words or symbols you like. If you click on any of the D.C. or D.S. type symbols you will see they have special fields in the inspector that tells what their purposes are and the map MuseScore will follow.

Use the To Coda and then change its text to the Coda sign, either by using the F2 palette or by copy/paste it from the real Coda

Was reported as now understood and fixed in the Facebook support group: https://www.facebook.com/groups/musescore/permalink/2459593504066953/?c…{"tn"%3A"R"}

@ Richard Tabnik...
You wrote:
but don't musicians expect to see two coda signs...

If you frequently use this style of notating both the 'To Coda' and the 'Coda' with the same coda symbol, you can save the modified 'To Coda' in a custom palette. This way, you won't have to keep changing the 'To Coda' text.
To avoid confusion in the palette, you can separate them from each other and/or give them different names.

To add an existing score element (such as your modified 'To Coda' symbol) to a custom palette, press and hold Ctrl+Shift, then drag the symbol onto the palette.
See:
https://musescore.org/en/handbook/palettes-and-workspaces#custom-palett…

Regards