Hi,

Try this code below to adjust the width,

th.o_column_sortable[data-name="field_name"]

{ 

width:150px !important; 

max-width:150px !important;

 } 

Hope it helps

Hi, 
define scss file in your module and add the following lines

.manual_entry_tree table.o_list_table thead th[data-name] {

  width: 150px !important;

  white-space: nowrap;

  overflow: hidden;

  text-overflow: ellipsis;

}

.manual_entry_tree table.o_list_table tbody td[data-name] {
  width: 150px !important;

  white-space: nowrap;

  overflow: hidden;

  text-overflow: ellipsis;

}

then on your tree use class="manual_entry_tree"
make sure you have added the scss file in assets-> web.assets_backend

This solution worked for me.

This is how I used it:

I added a new class to the tree view (In my case, it was Description field in sale order lines)

    order_line_tree

Used following scss

.order_line_tree > table > thead > tr > th.o_column_sortable[data-name='name']{
  width:200px !important;
  max-width:200px !important;
}

Thank you for the help :)

Thanks cybrosis, can you give more detailed information ?