[BUG] Some Live2D characters get stuck at "Loading model motions"

[bashekis]

When in the Live2D editor (https://sekai.best/l2d), some characters don't appear/load, and instead get stuck at "Loading model motions". I tested it on Firefox for Windows 10 and Microsoft Edge, and they both have the issue.
Here's a list of the characters I observed to be affected by this issue (NOTE: I've tested this with all the sub-characters but not the main ones so apologies if any were missed)
sub_airichildblack
sub_anfather_live
sub_anfather_rw
sub_aratablack
sub_divablack
sub_miu_cloth
sub_nagi_black
sub_nagi_live
sub_partner_live
sub_partner_rw
sub_riho_black
sub_yuukablack