Previously, the multi-record selector dropdown occupied an entire line. This commit addresses this issue by applying the `flex: 1 0 1rem;` property to the auto-complete dropdown. This adjustment confines the dropdown to the necessary space. If the space available is less than 1rem, it will wrap to a new line. Task ID: 3607067 closes odoo/odoo#146919 Related: odoo/enterprise#53071 Signed-off-by: Pierre Rousseau (pro) <pro@odoo.com>