Great example why one shouldn't do this kind of stuff late at night...I totally missed the "for locked bootloader" part :/
I unlocked the bootloader a while ago, had root and twrp. Then got the most recent update ota. With that I lost root and had terrible battery life. Flashed slims latest custom rom, runs great but still no root (and wrong ppi settings)...flashing root through twrp did surprisingly not work out...
...that's where I gave the newest motochopper here a try...now stuck on the bootloader screen after tool runs successfully ...
Ah. That's what you did...
So yeah... Don't use a root exploit on a custom ROM.
Was the slimrom you flashed a 4.3 version? If so, that's why your root wasn't working - special stuff is needed for 4.3 root.
You can probably flash a clean slimrom build then flash the latest SuperSu zip to get your root back...
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