and for a long time may not be, because the problem is in the wallet:
"difficulty" : 0.00001526
and diff never changes for a long time.
and in the wallet there is always some mistake
2018-01-01 07:11:34 GUI: libpng warning: iCCP: known incorrect sRGB profile
2018-01-01 07:11:34 GUI: libpng warning: iCCP: cHRM chunk does not match sRGB
2018-01-01 07:11:34 GUI: libpng warning: iCCP: known incorrect sRGB profile
2018-01-01 07:11:34 GUI: libpng warning: iCCP: cHRM chunk does not match sRGB