Ground-space interferometer RadioAstron provides unique opportunity to probe detail structure of the distant active galactic nuclei at $mu$as scales. Here we report on RadioAstron observations of the BL Lac object S5 0716$+$71, performed in a framework of the AGN Polarization and Survey Key Science Programs at 22 GHz during 2012-2018. We obtained the highest angular resolution image of the source to date, at $57times24 mu$as. It reveals complex structure of the blazar jet in the inner 100 $mu$as, with emission regions that can be responsible for the blazar variability at timescales of a few days to week. Linear polarization is detected in the core and jet areas at the projected baselines up to about $5.6$ Earth diameters. The observed core brightness temperature in the source frame of $geq2.2times10^{13}$ K is in excess of theoretical limits, suggesting the physical conditions are far from the equipartition between relativistic particles and magnetic field.
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