fade transition of tabs component is too slow

[rinick]

compare the animation speed between bootstrap and bootstrap-vue:
https://bootstrap-vue.js.org/docs/components/tabs/
https://getbootstrap.com/docs/4.1/components/navs/#nav-tab

both using transition: opacity .15s linear; but bootstrap-vue takes about 0.3 seconds instead of 0.15.

seems it wait for fade out finish and then start fade in, the blank time makes user feel that content is not ready. I tried changing the time to 0.07s fadeout + 0.07s fadein, total time is 0.14s, but the blank time in the middle still feels weird.

if it could do a crossfade, and start fade in fade out transition at same time, it would look much better

[rinick]

I just realize it's impossible to show 2 tabs overlap with 2 fade effect happening at same time without big layout change.
maybe a easier solution is do it exactly like bootstrap: hide the first tab instantly with no effect and only use fade on the show effect