ZOOM or Audio thumbs (from 2018-11 until 2019-12)

hi,

big problem for timeline 2.0 is not resolve issue long time..from date 2018-11-18 until now 2019-12-06, is not resolve issue..i dont know where is problem from..? j-b-m thinks that is issue from audiothumbs..but i cant find true issue from task process because is total frozen or blocking all processes..

• i use "use placeholders for missing clip" this mean i have not real file in computer but there is issue same blocking total.. instead if i have real clip..result same issue superslow (i was used pc dual xeon) not blockign..because has 32GB of ram..but not resolved (from 2018-11-18)..(see file screen record old)vokoscreen-2018-11-09_11-38-56

but now 2019-12-06,(kdenlive version:kdenlive-20.03.70-0cc2342e-x86_64.appimage) result same issue (not resolved) but pc is Apple (intel i7 3770s, 8gb ram) computer is totally blocking or FROZEN..

i send here file project: 1-test-zoom-10.kdenlive

so this issue level high critical..