It's not necessary, because if there's a problem if there's a problem it will fail.Already happening, thanks Read it somewhere else (5-6 actually ... don't know if that's neccessary).
But better make sure with 2 dumps than be sorry.
So that error may be an sd card busy error. I've already added a small wait when retrying in writing for the next version. Hopefully it will fix the error.
I still want to add a verification check.
Maybe I can do it today.
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BTW, the support of 2 font sizes is proving a lot of work, but I think I'll manage to release it today.