Table: Add filter-placement for table filter Popper

[qpxtWhite]

Table: Add filter-placement for table filter Popper;
If the column is too wide, the popper's position will be improper;

https://jsfiddle.net/whitewang/obpsLcva/7/

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[Leopoldthecoder]

Though I don't know why, this problem seems no longer exists in Vue 2.3.0: https://jsfiddle.net/obpsLcva/8/

Could you check if the above demo works fine for you?

[qpxtWhite]

@Leopoldthecoder the problem is still on my firefox and chrome
Please see the screenshot