Block download modal stops tracking at ~17000

[seriouscatsoserious]

I'm unsure why but at around ~17000 blocks the active downloads modal item for IBD disappears, even if there is more blocks downloading as evidenced by the console. This is a cosmetic issue. I suspect it might be due to that initial 17000 being hardcoded or tracked in memory somewhere that I forgot about, as when I first started working on this feature, that was roughly the block height.