Before this commit, the <hr/> in Discuss and Chatter
were not visible.
These <hr/> had no height but had a border. The border showed the
separator.
With the redesign of web client, <hr/> now have opacity of 25%.
This combined with borders being lighter made these separators
barely visible.
This commit removes border on these <hr>, which makes them use
their default visual, which is the same as a border.
closesodoo/odoo#121378
Signed-off-by: Sébastien Theys (seb) <seb@odoo.com>
Alexandre Kühn
d7d7f84ff2