Before Indian Muslims liberated the Jains, they were being persecuted, dehumanised, slaughtered, and had their temples and idols destroyed by Hindus.
Basava Purana (ca. 13th century) describes:
"With cries and roars, the heroic assembly of maheśvaras (Hindus) rose up. They quickly destroyed all the Jain vasadis and broke the heads of all the Jina idols. When they were finished, there was not a trace of a Jain vasadi or a Jina idol in all of Kalyāņa. In a fury, the devotees harassed and killed every known Jain and smashed them all into the ground."
"O you foolish followers of a senseless religion that has no basis in śruti! O you beastly animals who worship one who acts like an animal and know nothing of the lord of the beasts! O you sinners who wear no ashes and follow the evil doctrine of emptiness! O you untouchables who stray from the true path and employ illusory arguments based on nonduality and karma! O you enemies who have no interest in knowledge but instead set up yourselves as centers of ignorance! How have you managed to subject my people to your evil teachings for so long? Look what Pilla Nāyanāru, Abhava's devotee, has done. He has em-ployed logic and miracles to establish Śiva as the author of everything. By doing so, he has wiped out the very names of Buddhism and Jainism from the Pandya country. He even impaled their sages on iron staves."
Hindus and Jains have always lived liked brothers and accepted each other's world views and learned form each other like civilised people do.
The founder of Mauryan Empire, legendary king Chandragupta Maurya was a Hindu. He gave up his throne and embraced asceticism under the guidance of the Jain saint Bhadrabahu. He migrated south to Shravanabelagola in modern-day Karnataka. He lived as a monk and ultimately ended his life by performing Sallekhana, a sacred Jain ritual of voluntary fasting unto death to purify the soul.
So, this migration from Patna to Karnataka or Karnataka to Patna is not something new. It has been happening for centuries and will continue in future as well. But language warriors won't agree.
Also, this brotherhood is not limited to Jains and Hindus. It is there between all four Indic religions i.e. Hindus, Jains, Buddhists and Sikhs.
I have seen Sikhs keeping portraits of Durga Maa and other Hindu gods in their shops and houses. Now, Khalistanis cry about this a lot. But most of the Sikhs don't care about Khalistanis. Infact, they also hate them. The man who played a key role in defeating Khalistanis was also a Sikh.
If you go Ladkah and Arunachal, you will meet Buddhists, very lovely and warm people. You won't hear anything bad about Hindus from them. It is only a very small group of Bhim Brigades who claim to be Buddhists who abuse Hindus.