that occurred on February 13th 2011 (maximum at 17:28 UT), whereas the last one was a M5.6-class flare on August 24th 2015 (maximum at 07:26 UT). Between these two dates we selected 54 WLF candidates (including the two already mentioned) with a maximum X-ray class of X5.4 (March 6th 2012). The weakest WLF candidate out of 54 was classified as M1.8 (July 5th 2012) and was included in the analysis, only because it was followed by a M6.2-class flare 50 minutes later and was accidentally recorded in the same investigated datacube.

For each flare candidate we tracked a 3-hour datacube around the time of the flare maximum by using publicly available JSOC[^1] tools. The cube was tracked with a Carrington rotation rate at a full HMI resolution (pixel size of 0.5") and we focused to region centred on the flare location (as given by GOES data and verified in NASA’s SolarMonitor[^2]) with a field-of-view of 768$\times$768 px. We retrieved not only $I_{\rm c}$ data, but also line-of-sight magnetograms that are both spatially and temporally aligned in order to perform a fast analysis of the magnetic field in WLF candidates. Such datacubes were prepared for a search of $I_{\rm c}$ brightenings 