Bug 29528 – "border-collapse: collapse;" tables with unnecessary colspans draw screwey borders

• Component: CSS
• Status: UNCONFIRMED

[Rod]

Created attachment 39832 [details]
example of the problem

This looks like it might be a duplicate because all of the other border-collapse bugs filed seem to do similar kinds of things but I couldn't find a bug that was specific to this issue.

If you have a table that is border-collapse:collapse and have cells that have colspans that are technically unnecessary, the border of the table will be drawn incorrectly and may also be drawn around cells inside the table erroneously.

This bug has been observed on Chrome and Safari for some time now, including the current versions of each (Chrome 3.0.195.21, Safari 4.0.3). I have no tested on current WebKit, sorry.

Attached is an example of what happens, including a small table at the bottom with some javascript that extends the table and makes the colspans necessary, the problem disappears (if you extend the table with even more unnecessary colspans then the problem persists).

Note that the example at the bottom demonstrates why you may have a table with seemingly unnecessary colspans. I have a table that contains a form that does progressive-disclosure as it is being filled out, the colspans are unnecessary when only the top of the form is visible but other rows make the colspans necessary.

[kiravi]

Even I find tables are not rendeded right in chrome.  Using the lastest chrome dev build as of today.
18.0.1017.2

[kiravi]

Created attachment 124470 [details]
Attached from kiravi on latest chrome dev branch.

This is the file that depicts the issue.  Opera renders is right in the latest 12.0 branch.  So does Firefox