I know this is an old thread but I am having the same issue. I am using attachHeader method and have a #master_checkbox in column 0. It is automatically padded/aligned to the right. I have tried the advise you gave here and it does not work. It is applied to the td element but, the checkbox is contained in a div inside the td with a class of “hdrcell” that has the padding-left:10px attribute.
I also tried the example listed here but this apparently only applies to the setHeader method.
I have also tried adjusting the margin and padding in the td cell but nothing I’ve done seems to work.
it produces a checkbox but, it is no longer a “master_checkbox” in that it does not control the checkboxes in the column. It is also still not centered due to the 10px padding-left in hdrcell.
the solution with the style attribute of the attachHeader method should work correctly.
If the problem still occurs for you could you please, provide with a complete demo or a demo link, where the problem can be reconstructed locally.
Also, please, make sure that you have not redefined the global css styles on your page.
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