Stuart Noble wrote:

Linseed should always be
overpainted where it meets the glass, this painting fills the hairline
crack its prone to. It may sound a bit crude but it works well enough
in practice.

Look, the main requirement for any material sitting at the bottom of a
sheet of glass where it joins a piece of wood has to be that it doesn't
crack. Linseed putty cracks. Get over it.

Good luck with your acrylic then.