Can replicate this easily now, and unchecking "Real-time drawing and editing" indeed helps

The workaround for this bug is to disable "Real-time drawing and editing" in the preferences. It's clear that this feature is the cause.

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このバグの回避方法は、環境設定の「リアルタイムの描画と編集」を無効にすることです。この機能が原因であることは明らかです。

Sorry it took a while. Here is a file and video. It's basically just a new file where I created a black box in the background to easier see the artwork. In the video I'm pasting the artwork in, then you can see me dragging the corners to enlarge. You can see it messes up. Then I hit command Z and it's still pretty messed up after undoing.

I have no problem in the previous update, but I noticed with the current, strokes and effects won't scale based on the original thickness even if the preference setting has been ticked.

See attached image for a sample. In "scale to small" you can see that the stroke is thinner than the original, and in "scale to large" the stroke gets thicker than the original.

It gets frustrating as I have to manually scale all the elements just to make it consistent/cohesive :(

OS: Windows 11
Adobe Illustrator: v 29.8.1

> To be honest I've never found it useful to not scale strokes.
Trust me, there are numerous examples where this is useful. More of it — this is my personal preferred mode of treating strokes. Workflows differ and Ai is versatile.

Apart from this — I get the stroke gets scaled twice as it shoul... but I can’t reproduce this. I presume there is something peculiar with the artwork itself...
If you can, please make a duplicate of the artwork, strip details until the bare minimum required to reproduce the behavior, and share the this test file here.
A small video showing the exact approach to resizing it would be helpful as well.

Yes, scale strokes and effects is checked. To be honest I've never found it useful to not scale strokes. I mentioned on another post that sometimes it becomes unchecked by itself but I did check before I created the example I included. Maybe I didn't explain it well enough. The left logos still have strokes specifically around the background H. The logos on the right the strokes are converted to outlines. They are all reduced down from a larger size. The top two were reduced by numerical value typing in 50% then enter. The bottom two were reduced down roughly 50% by dragging from the upper right corner holding option shift for constraints. You can see the bottom left logo's stroke outline is roughly half the size it should be. Both of the logos on the left are still strokes. I'm on a M1 Mac Pro and Illustrator is the latest version (not beta).

Mike, not sure I follow.
When you check Preferences > General, is Scale Strokes & Effects option enabled for you?
Do you check this option when using the Scale dialog? The option is global. Once checked in this dialog, it gets enabled across all the documents.
If this is not the case, please share a test file and a video recording of the workflow you are using.

When scaling artwork by dragging a corner (I used the upper right corner) the strokes get messed up. In the included image the left logo has strokes and fills. The right logo has strokes converted to paths. When I reduce the image down 50% using the numerical scale menu by double clicking the scale tool it turns out fine as the top 2 show. Below that are 2 logos I scaled by dragging the top right corner and holding option shift keys. The logo with the stroke shows the outline being much smaller. If I select the 2 the top stroke says 7pt and the bottom image shows 3.5.

外野から失礼します。
私も同じ状況で色々検証したところ、図形でもグループ化されたものに対して同様のオフセット効果をつけた場合、拡大および縮小で意図しない比率に変わってしまいます。
最悪なのはcommand+Zで戻っても大きくなった比率を維持してしまう点です。
拡大して戻る、もう一度拡大して戻る・・・を繰り返すとどんどん太くなります。（縮小だとどんどん細くなる）

この状態だと私の仕事内容では使い物にならないのでバージョンを29.5.1に落として使用しています。
アップデートがあるたびに期待してアップデート→バグが直ってなくて元に戻すということを繰り返しています。

ご検証ありがとうございます！
ただ、「プレビュー境界を使用」を無効にしても挙動は同じでした…。
他のアプリを多く立ち上げていることが多いので
それも原因かもしれないですね…？
自分のパソコンの原因でないことが判明したので
ひとまず前のバージョンを使用したいと思います。
お忙しいところありがとうございました。

Thank you!
Indeed, I can reproduce this issue, using 29.5.1 (no problems noticed) and the latest Beta 29.8 (two GIFs with two different results).

Steps are:
1. Enable both Use Preview Bounds and Scale Strokes & Effects options, either in Preferences dialog or Properties panel (with nothing selected).
2. Create a duplicate of the object
3. Using Bounding Box, scale the object down with Shift held
4. Scale it up, ideally to match the original size

Results.
29.5.1 makes almost the same appearance. Relative values are consistent, the artwork looks like a copy of the original.
29.8... both Offset Path effects (white and black) assigned to a group of two text objects within the parent group get scaled wrong — they become either too big or too small, compared to the other appearance!

I assume the Beta works the same way with it as the GA build 29.6 (and 29.7 is on the way to become GA) — I will test it later.
I noticed the Beta sometimes was able to scale the artwork correctly... and the more other apps I run in the background, the more the chance of the miscalculation... but perhaps it’s a false observation. 29.5.1 though never did it wrong in ~7 attempts I checked it with.

Disabling Use Preview Bounds eliminates the behavior, and the scaling becomes consistent.

Please comment if I got this correctly!

該当データです。環境設定は有効になっていました。
ご確認お願いします。

Again, hard to tell without looking at the specific appearance stack you used and the options enabled in Preferences.
To be fair, I still struggle to fully understand problem you are mentioning... I’m surely noticing the changes with the appearance when you scale the object down... I believe these should stay consistent, with Scale Strokes & Effects enabled, but I can’t reproduce it.
Please share this file here (without the font used, I don’t think it matters) — I’ll try to compare how 29.5.1 and 29.6.1 behave with it.
Thank you for the report and the patience.

もしかしたら特定の文字のアピアランスがおかしくなるのかもしれません。
図形は平気だけど動画の文字は挙動がおかしかったです。

Not sure yet, I don’t think I can follow the problem...
Kindly provide a short video or a GIF to show how it behaves at your side, to try to reproduce it at the team’s side.

図形や文字の幅をアピアランス→塗りを指定→パスのオフセットで
幅を変更しています。ｖ29.61と29.6でイラレを使用すると
縮小などをした際に幅の比率が変わってしまいます。(線幅と効果拡大縮小もチェック済み)
※線で作成した図形や文字は比率を守ってくれます
29.51を使用すると問題なく拡大縮小ができます。
これはバグなのでしょうか？