[Plugin] Epub3 E-Reader Plugins for Sigil

[RbnJrg]

Originally Posted by KevinH

So perhaps the issue is missing or damaged fonts with bad font metrics. Not sure here.

No Kevin, is not due to bad font metrics. By removing "Times New Roman" as font for the epub body (and using the default system font for serif) the blank page is still there. The setting for Bibi are the same for Windows and Linux (see my previous post), so the issue must be originated by something in the setting of my Sigil or Linux but I can't guess what!

[RbnJrg]

Originally Posted by DiapDealer

If, like I suspect, he's using the legacy ttf-ms-fonts package from the Arch User Repository, that's very likely the culprit.

I think your post and mine crossed No, the font is not the culprit; by using the system serif font the blank page is still there.

[KevinH]

What happens when you change the Window size?

Or wipeout the Bibi folder you copied from Windows and reset to defaults and try that. What happens then?

Copying the Windows Bibifolder for settings over may not be a good idea depending on what exactly Bibi is writing to its own settings.

[RbnJrg]

Originally Posted by KevinH

What happens when you change the Window size?

At full window (double page), no blank pages at all. When wider is the window, less blank pages. With a width of 1100px (and the same height of 600px), no blank pages at all. The curious thing is the problem is only with Bibi; Readium and EpubJS display the epub as is expected, no blank pages. Also Calibre displays correctly the epub like Foliate (Linux versions).

Or wipeout the Bibi folder you copied from Windows and reset to defaults and try that. What happens then?

The blank pages are there

[RbnJrg]

Originally Posted by KevinH

What happens when you change the Window size?

The issue is something linked with Sigil and Bibi running on Sigil. I opened the epub with Bibi running on Firefox (linux version) and no problem.

First I opened in Firefox the file index.html that one can find in:

/home/user_name/.local/share/sigil-ebook/sigil/plugins/BibiReader/bibi/

and then I drag and dropped the epub in that page. No matter if the browser window is resized, no blank page is generated. You can explore the epub code by pressing F12 and all works fine there. So, it must be something with my Sigil and Bibi running on it. If it were something linked with Linux, the epub wouldn't be correctly displayed in Calibre, Foliate or Firefox. And if it were something linked with Sigil, then Readium and EpubJS would also generate blank pages, and they don't.

[KevinH]

If you see the extra pages go away with Window sizing, it is probably a bug in Bibi that this combination (Chrome/QtWebEngine) just tickles.

Can you try your Firefox trick with a Chrome browser at the Window size that causes problems? Or try Falkon (also QtWebEngine based).

[RbnJrg]

You were right! I did the try with Falkon and when I went at the window size that caused my issue, also in the browser the blank page was generated. It seems that the combination Chromiun/QtWebEngine triggers the bug. Could you do the test in your Manjaro with Falkon to see if the epub (by opening it) with Bibi running on Falkon (not running maximized, just in a window) generates blank pages?

Originally Posted by KevinH

If you see the extra pages go away with Window sizing, it is probably a bug in Bibi that this combination (Chrome/QtWebEngine) just tickles.

Can you try your Firefox trick with a Chrome browser at the Window size that causes problems? Or try Falkon (also QtWebEngine based).

[KevinH]

I will give it a try tonight. What exact Window Size causes the issue?

- Update:

Saw your images with 430 x 600 and tried that with Sigil and saw no extra pages. Tried loading that epub into Falkon and Chrome with a whole bunch of window sizes and saw no extra pages with either of them. So I am just not seeing what you are seeing. My Manjaro build uses their latest Qt5.

So please try the following:

- make sure the Bibi setting for zoom has been reset to default

- try removing the following folder if it exists:
~/.local/share/BibiReader/QtWebEngine

Other than that, I am out of ideas.

[DiapDealer]

I know you (@RbnJrg) recently built Sigil 1.9.10 from my instructions. Did you build the Qt6 version or the Qt5? I just want to try to get as close to your setup as possible.

Did you also remove the problematic repository version of 1.9.10 for good measure?

[RbnJrg]

Many thanks for your patience Kevin. I erased the folder you said (but when I run Bibi is regenerated) and the zoom already was at default level. No case, the blank pages still are there

Originally Posted by KevinH

I will give it a try tonight. What exact Window Size causes the issue?

- Update:

Saw your images with 430 x 600 and tried that with Sigil and saw no extra pages. Tried loading that epub into Falkon and Chrome with a whole bunch of window sizes and saw no extra pages with either of them. So I am just not seeing what you are seeing. My Manjaro build uses their latest Qt5.

So please try the following:

- make sure the Bibi setting for zoom has been reset to default

- try removing the following folder if it exists:
~/.local/share/BibiReader/QtWebEngine

Other than that, I am out of ideas.

[RbnJrg]

I built the Qt6 version and yes, I previously removed the official (and problematic) version of Sigil 1.9.10.

Originally Posted by DiapDealer

I know you (@RbnJrg) recently built Sigil 1.9.10 from my instructions. Did you build the Qt6 version or the Qt5? I just want to try to get as close to your setup as possible.

Did you also remove the problematic repository version of 1.9.10 for good measure?

[DiapDealer]

Ok, thanks.
And I assume that you installed PySide6 since the latest version of BibiReader is working (for the most part)?

[RbnJrg]

I inspected the epub and Bibi displays the .xhtml files with the following code:

<div class="spread-box reflowable spreaded" style="width: 7845px;">
	<div class="spread" style="height: 361px; width: 7845px;">
		<div class="item-box reflowable loaded" style="background-color: rgba(0, 0, 0, 0); background-image: none; background-repeat: repeat; background-position: 0% 0%; background-size: auto; height: 361px; width: 7845px;">
			<iframe class="item" scrolling="no" src="" style="background-color: rgba(0, 0, 0, 0); background-image: none; background-repeat: repeat; background-position: 0% 0%; background-size: auto; padding: 48px 24px 24px; height: 289px; width: 5182px;">

				<html xmlns="http://www.w3.org/1999/xhtml" class="Linux Chromium Blink Chrome bibi-flick-active bibi-flick-scrollable bibi-pinch-active bibi-columned" xml:lang="UND" lang="UND" style="background: transparent; height: 289px; column-fill: auto; column-width: 475px; column-gap: 48px; width: 5182px;">
					<head>...</head>

					<body style="background: transparent; font-size: 1rem;">...</body>
				</html>
			</iframe>
			<span class="page"></span>
			<span class="page"></span>
			<span class="page"></span>
			<span class="page"></span>
			<span class="page"></span>
			<span class="page"></span>
			<span class="page"></span>
			<span class="page"></span>
			<span class="page"></span>
			<span class="page current"></span>
		</div>
	</div>
</div>

I thought that the issue was caused by the following lines:

			<span class="page"></span>
			<span class="page"></span>
			<span class="page"></span>
			<span class="page"></span>
			<span class="page"></span>
			<span class="page"></span>
			<span class="page"></span>
			<span class="page"></span>
			<span class="page"></span>
			<span class="page current"></span>

and I erased them but without luck, the blank page remains.

[RbnJrg]

Originally Posted by DiapDealer

Ok, thanks.
And I assume that you installed PySide6 since the latest version of BibiReader is working (for the most part)?

Yes, I installed PySide6. I had to, because Bibi didn't run and it said "no pyside6 module found". After installing PySide6 all worked fine.

[DiapDealer]

Is your Arch machine virtual (running on a host OS) or is it a physical machine? I ask because Virtualbox video drivers can often introduce flaky behavior/artifacts where WebEngine is concerned. Epubs used to render upside down in Sigil's Preview when 3D acceleration was enabled in the video driver settings for the guest machine in Virtualbox.

Basically, I'm trying to determine what is different between our machines. We've got virtually identical builds of Sigil 1.9.10 on Arch Linux, so video hardware/drivers is about the only thing left that I can think of. The fact that other chrome-based renderers are exhibiting the same behavior lends credence to the notion of there being some issue with chromium/WebEngine and your video card/drivers.