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The recently discovered GRB 210905A is the highest redshift GRB for which an early comma high-S-N comma mid-high resolution afterglow spectrum has been obtained. In addition to providing the redshift comma this spectrum exhibits numerous metal lines and a complex velocity structure spanning virgul360 km-s comma and blueshifted by virgul1000 km-s from a tentative Ly-a emission line. Modelling of the Lyman-alpha damping wing reveals the host column density comma and puts constraints on the neutral fraction of the surrounding intergalactic medium. Analysis of the abundances gives an average metallicity ZvirgulZsol-20. In addition comma the afterglow of this GRB started bright and has declined slowly comma implying a late jet break. This suggests a wide jet and hence a particularly high energy event comma perhaps indicative of an unusual progenitor star. Here we seek HST WFC3-IR F140W imaging to obtain a final late-time point on the afterglow light curve to constrain any break comma and an image after the afterglow has faded comma to provide a subtraction template and characterisation of the host galaxy. This would make it the first galaxy at z>6 detected in emission for which detailed absorption line abundances for multiple species are available.