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The configuration of toroid belt, a longitudinally elongated region around which active regions (ARs) cluster, has been shown to be an indicator of intense activity, namely complex ARs appearing at the locations in the North and/or South toroids, "tipped-away" with respect to each other. On the other hand magnetic helicity has been used as an indicator of flare activity in active regions. As solar cycle (SC) 25 approaches its peak, a number of significant (X-class) flares have been produced. Here, we investigate the circumstances under which two of the most flare-prolific active regions of solar cycle 25, namely ARs 13590 and 13514. Two aspects of the evolution of these active regions are investigated: the global-scale magnetic toroid configuration and small-scale magnetic field morphology and topology, prior, during and after the onset of major flares. The global morphology of the solar magnetic fields near intense flares is studied in terms of the spatial distribution of active regions on magnetic fields synoptic maps. On active region scales we analyse the magnetic helicity accumulation as well as its current-carrying and potential components. Our results are consistent with major flare prolific ARs from solar cycles 23 and 24, namely, we observe a consistent dominance of current-carrying magnetic helicity at the time of major flares. Evolution of global magnetic toroids, indicating the occurrence of flare-prolific active regions in the tipped-away portion of the toroid, together with the local dynamics of complex active regions, could provide a few weeks' lead-time to prepare for upcoming space weather hazards. |