colspan is ignored on table cells

[ruir6o]

Describe the bug
I have created a table for listing the tracks in an album, which uses a single cell that spans all of the columns when multiple disks exist in order to separate the tracks from one disk from the other. However, when Metro transforms the table it removes the colspan attribute, meaning that the first column (with the track number) suddenly grows in width and disrupts the whole intended layout.

To Reproduce
Example. If you inspect the elements that specify the CD number you'll see that the colspan attribute was removed. Adding it manually with the developer tools to both CD entries will then resize the table to the expected layout.

Expected behavior
The colspan attribute should be retained in the <td> element that defines it.

Screenshots
Current behaviour:

Expected behaviour (manually added the colspan attribute):

Desktop:

• OS: Windows 10
• Browser: Opera GX 88.0.4412.85
• Metro Version: 4.5.1