Hi @jgregory105 ...
Merging and splitting cells in a table seem to work fine for me. For example, in a new page in my "sandbox" Canvas course, I created a 3 x 3 table. While still in editing mode, I selected the top two left-most cells in the table and then selected the "Merge cells" option from the "Table" tool. The two cells merged together as one. Keeping my cursor in that merged cell, I then clicked on the "Split cell" option from the "Table" tool, and my table returned to the 3 x 3 shape that I originally created.
I hope this helps, Jane.
Took me a while to find this as I was trying to merge the cells by using the pop up table options that pop up at the bottom of the table.
All you need to do
1. select / highlight the two table cells
2. click on the table icon in the editor
3. select Cell / Merge Cells
Thank you for your input! I actually discovered that the problem was my browser. Once I switched from using Firefox to Internet Explorer, the table editing features all worked fine.
I just checked and it looks like it is possible to split cells. You have to click into the merged cell, then you can select the Table icon in the RCE, hover over Cell, and pick Split cell.
I didn't see anyone discuss accessibility in the posts above. Merging cells in tables can cause accessibility issues with screen readers; Penn State has a great page on table accessibility and they say:
Even with headers properly marked, if cells are merged, a screen reader could find it difficult to determine which cell when cells become merged. Therefore it is recommended not to merge cells.
I hope this helps!