iPadOS UI Bug: Highlighting Visual Vibration

nbabarskis · 2026-03-03T21:37:08+00:00

I am experiencing a peculiar visual jiggle/vibration when highlighting text in the iPadOS app. I experienced this issue while using an apple pencil to highlight text. As I drag my pencil to highlight text there is a noticeable “vibration” in the bubble that zooms in on the text that is being highlighted. A recorded a video of my display and can share if needed.

mvasilak · 2026-03-04T09:37:25+00:00

Please share the video here or by mail to support@zotero.org and mention this thread.
Please also let us know which version of the Zotero app you use, which iPadOS version, which iPad model and pencil. Is this happening with a PDF or ePub/HTML item?

mvasilak · 2026-03-06T09:40:04+00:00

Hey @nbabarskis, thanks for the video, we can reproduce the issue. As you corrected in your email, this only happens with active highlight tool, when selecting with a finger, not with a pencil. The pencil is accurate enough, but with the finger the selection sometimes may jiggle to the next line.

This is part of a third part library we use, so we are going to forward it to them and wait for their feedback.

Keep in mind that selecting without an active tool, and then selecting e.g. highlight from the selection menu, seems to not produce this jiggle.

nbabarskis · 2026-03-07T03:02:48+00:00

I experienced the giggle when using an apple pencil with the active highlight tool selected. No jiggle when using finger or pencil with the active highlight tool deactivated.

mvasilak · 2026-03-07T08:32:42+00:00

Sorry about my confusion. In my tests, I saw the jiggle when highlighting with my finger, but not when highlighting with the pencil. Since you witnessed it also with the pencil, this might be file specific. Does this happen with all files, or just specific ones? Can you share the file that you recorded the video with by mail?

nbabarskis · 2026-03-07T12:20:02+00:00

I think you might be right. i tested the apple pencil on an epub and on a dissertation pdf file (not as complex typesetting as a journal article) and had no jiggle. I sent an email with the attachments for the files that do have a visual jiggle.