Fractional polarisation against total intensity (Stokes I) flux density for: LoTSS sources (black points); pulsars discovered or detected through the TULIPP survey (squares); candidates observed and searched for pulsars in this work (blue circles); and known pulsars (red circles). Left: linearly polarised sources from the RM GRID (O’Sullivan et al., in prep.). Right: circularly polarised sources (absolute values) from V-LoTSS (Callingham et al., in prep.).