Writer 7.6 scrolls very slowly in equation-heavy documents

[KlausB]

Version: 7.6.0.3 (X86_64) / LibreOffice Community
Build ID: 69edd8b8ebc41d00b4de3915dc82f8f0fc3b6265
CPU threads: 12; OS: Linux 5.3; UI render: default; VCL: gtk3
Locale: de-AT (en_US.UTF8); UI: en-US
Calc: CL threaded

After upgrading to 7.6 I am seeing an issue, where a document containing many equations will scroll very slowly, starting in safe mode with a factory-reset profile did not help.

By contrast, no such issue is present when I use

Version: 7.3.5.2 / LibreOffice Community
Build ID: 184fe81b8c8c30d8b5082578aee2fed2ea847c01
CPU threads: 12; OS: Linux 5.3; UI render: default; VCL: gtk3
Locale: en-US (en_US.UTF8); UI: en-US
Calc: CL

The problem is weaker but present when using

Version: 7.4.7.2 / LibreOffice Community
Build ID: 723314e595e8007d3cf785c16538505a1c878ca5
CPU threads: 12; OS: Linux 5.3; UI render: default; VCL: gtk3
Locale: en-US (en_US.UTF8); UI: en-US
Calc: CL

Is there anything I can try other than downgrading? I specifically want to avoid downgrading due to bug 99225 being present in 7.3.

[ajlittoz]

Can you attach a small sample (1-2 pages) of your file to see how you format your document?

[KlausB]

anonymized.odt (201.6 KB)

By chance I am able to provide an only slightly redacted document in this case, since it was mostly the start of a literature review, without many project-internal notes yet. I have removed any references to the actual project, that were already inside, and it reproduces the problem when scrolling around the end of the document.

[ajlittoz]

Though you have direct formatting, you text is fairly correctly styled. I found nothing special in the sample, so your slow behaviour may be a consequence of your use of Zotero (which add a lot of direct formatting by itself).

You have a reference error for “fig. x” in “2 Background theory”.
Try to remove your remaining direct formatting (it will not change dramatically the behaviour but would allow you to better control your document).
Are you sure the Math formulas are responsible? What about Zotero?

[KlausB]

@ajlittoz I do not actually use Zotero in this document. The bibliography is handwritten, because I now use JabRef, and couldn’t get the LibreOffice/JabRef connection to work.

[ajlittoz]

Your document, or a previous version, has been in contact with Zotero as shown by File>Properties, Custom Properties. This sample is not based on a template, but your real document perhaps is. Then the template itself may reference Zotero, though I doubt it considering citation contents.

Have you noticed if there is a threshold in the slowdown (depending on number of formulas)? I have no issue here and my PC is much weaker than yours (only 4 threads) but in version 7.5.5.2, kernel 6.4.12, KDE Plasma (VCL: kf5).

I don’t quite understand your cross-references to the bibliography because Edit Fields reports page number request (!) while they show the (correct) citation ID.

[KlausB]

Prior use of Zotero was the case, yes.

There is indeed a threshold. In this particular document for instance, scrolling on the second page is still mostly fluent, but becomes laggy on the third page. It gets worse when I zoom out such that multiple pages are visible at once, but doesn’t vanish when I zoom in.

The bibliography references are just bookmarks (created manually on the citation names) and text-references to bookmarks.