Window weld motor mounts question

Been wanting to try window weld in my rear motor mount. Does anyone know if this stuff will work the same? It’s like $6 a tube at Home Depot compared to the 3m brand weld which is $20 at Auto Zone. This stuff just says sealant and not weld, but it’s poly none the less. I just don’t want to waste my extra motor mount if this stuff is going to be really soft by comparison and not do what I want it to.

Just wondering if anyone has any idea weather this will work or not.

Thanks!