Remove dried bath oil in the bath

I got a beautiful rose oil for bathing. After the first use, I drained the water and then did not rinse it immediately, which led to the awakening the next day that a sticky film had formed in the whole tub.

I've tried to get rid of the mishap with regular bathroom cleaners, but even with heavy scrubbing, the oil was more stubborn than mine.

My saving idea was then to spray the bathtub with oven cleaner and I could watch how the film dissolved. After a few minutes exposure, I only had to rinse the tub thoroughly and wipe with a cloth and the tub looks like new.

I hope I can spare others a lot of work, if that happens to you too!