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[DC / Martian Manhunter] How has J'onn J'onzz dealt with his fear of fire over the years?

There had to have been more than one situation in his career as a superhero where he had to deal with fire whether directly or indirectly, yet even far into his career with the Justice League it's been observed that a mere match can terrify him. How does he deal or cope with it? How has he dealt with situations involving fire?
gpt
There was a Post-Crisis storyarc where J'onn decided to try and cure his fear of fire, after it rendered him helpless to assist the League and they nearly died because of it.

To this end, he enlisted the help of a reformed pyrokenetic supervillain named Scorch.

Through intensive psychic and physical training, J'onn was eventually able to rid himself of his weakness to fire.

Unfortunately, this kickstarted another JLA story, called "Trial by Fire" where, long story short, J'onn goes Dark Phoenix on the entire world.

As it turns out, the Martian fear of fire was genetically engineered into them by the Guardians of OA millions of year earlier.

Before that, they were actually a fire elemental species called "The Burning" who, in addition to all currently known martian abilities, could generate fire, and psychically fed off the destruction and violence they cause to grow stronger and reproduce.

The fear of fire was put into them as a way to save the galaxy from their proliferation beyond Mars, without completely exterminating their species altogether. The Green Martians' innate fear of fire has been what keeps them from reverting back to this savage and nearly omnipotent state.

J'onn removing those blocks from his mind causes him to revert to the form of a Burning, and he is taken over by the malicious persona of 'Fernus'. 

Fernus has all of J'onn's physical and telepathic abilities with no restraint, in addition to being able to grow stronger the more the Leaguers engage him in battle and the more destruction he causes. Superman concedes that J'onn is in arguably the strongest being on Earth by this point.

Fernus attempts to burn the whole world down in nuclear Armageddon and use the resulting fire and cataclysm to reproduce a new army of Burning who can conquer the galaxy.

He nearly succeeds but is narrowly defeated by the JLA thanks to essential help from Plastic Man, J'onn consciousness buried within him, and a sacrifice from Scorch.

At the end of the story, J'onn regains a weakness to fire, but only under the condition that if it's a 'fire of the psyche', which was kinda vague but seemed to basically mean fires which have already killed lots of people, or started by malicious intent.

At some point though, that just got dropped, and he was back to being weak against fire in general.