Can't Multi Select Large Playlist of Movies to Add to Collection

[denzoid 51]

I have a playlist of 1,075 movies in a smart playlist of movies from the 1940s. if I open the playlist and try to select all 1,075 to add to a Collection only some get selected. I have them sorted by title and I select the first title with the radio button then scroll to the bottom and while holding down the shift key (I'm on Windows using Edge) click on the radio button next to the last title but as you can see from the screenshot only 115 get selected. I've tried many times and each time a different number of titles get selected. Is this a bug or am I doing something wrong?

[GrimReaper 3971]

17 minutes ago, denzoid said:

I have them sorted by title and I select the first title with the radio button then scroll to the bottom and while holding down the shift key (I'm on Windows using Edge) click on the radio button next to the last title

How did you scroll to the bottom?

Tbh, never tried it on a playlist with so many items, but assuming behavior is the same as in library tab/virtual scroll: items are loaded in chunks (50ish pieces) as you scroll, meaning you need to actually scroll through all the items to have them loaded, not use slider and click last item, as in that case you're effectively loading 100-ish items (50ish at the start+50-ish at the end). In short: select first item>scroll with mouse wheel slow/fast enough that all the items get loaded as you scroll down>shift-select last item once you're at the bottom.

Edited March 3 by GrimReaper

[denzoid 51]

58 minutes ago, GrimReaper said:

How did you scroll to the bottom?

Tbh, never tried it on a playlist with so many items, but assuming behavior is the same as in library tab/virtual scroll: items are loaded in chunks (50ish pieces) as you scroll, meaning you need to actually scroll through all the items to have them loaded, not use slider and click last item, as in that case you're effectively loading 100-ish items (50ish at the start+50-ish at the end). In short: select first item>scroll with mouse wheel slow/fast enough that all the items get loaded as you scroll down>shift-select last item once you're at the bottom.

I was just using the slider to scroll to the bottom. I used your suggestion and scrolled down letting each page load as I went and it worked. All the titles were selected. Thanks for the help!

[Carlo 4543]

Scroll to bottom and select item.
Use CTRL-HOME to jump to top.
Multiselect the first item!

[denzoid 51]

10 hours ago, Carlo said:

Scroll to bottom and select item.
Use CTRL-HOME to jump to top.
Multiselect the first item!

Scrolling (not dragging or jumping) seems to be the key here (as noted by GrimReaper), and each page needs to load during the process.