Previsualisation broken

[roger64]

Hi

Since yesterday, on Archlinux, after a big Qt update (but not only it), I realized that previsualisation is broken on Sigil with all ePubs. It displays the files exactly as if there was no style sheet, even images are not displayed.

All these ePubs are correctly displayed with the Calibre editor and have no ePubcheck defect reported.

I have Sigil 1.2.1 with 5.15 Qt.

[KevinH]

If images will not load, then the resource locations are not being properly found based on the url provided when the xhtml is loaded.

My guess is either you are missing QtWebEngine pieces or they are not properly being found.

[roger64]

thanks Kevin

I just joined above the list of updated files. I shall reinstall Qtwebengine.

[KevinH]

Try updating again. You have qt-base updating to 5.15.0.1 in one place in the list and qt-base going to 5.15.0.2 but qt-webengine seems to not get that second update. Perhaps you updated during a time when qt packages were being updated and got a mix?

[KevinH]

Also you went from Sigil using Qt-5.14.x to Qt-5.15.x but I am not sure they are binary compatible. You may want to rebuild Sigil against the newer versions if updating does not do the trick.

[roger64]

Hi

I just followed the recommended updates. Reinstall changes nothing. Keeping low for the time being.

[roger@lenovo ~]$ sudo pacman -S qt5-base qt5-webengine
[sudo] Mot de passe de roger*: 
avertissement*: qt5-base-5.15.0-2 est à jour -- réinstallation
avertissement*: qt5-webengine-5.15.0-1 est à jour -- réinstallation
résolution des dépendances…
recherche des conflits entre paquets…

Paquets (2) qt5-base-5.15.0-2  qt5-webengine-5.15.0-1

Taille totale installée*:    208,79 MiB
Taille de mise à jour nette*:    0,00 MiB

:: Procéder à l’installation*? [O/n] O
(2/2) vérification des clés dans le trousseau      [######################] 100%
(2/2) vérification de l’intégrité des paquets      [######################] 100%
(2/2) chargement des fichiers des paquets          [######################] 100%
(2/2) analyse des conflits entre fichiers          [######################] 100%
(2/2) vérification de l’espace disque disponible   [######################] 100%
:: Traitement des changements du paquet…
(1/2) réinstallation qt5-base                      [######################] 100%
(2/2) réinstallation qt5-webengine                 [######################] 100%
:: Exécution des crochets de post-transaction…
(1/1) Arming ConditionNeedsUpdate...
[roger@lenovo ~]$

[KevinH]

Given Qt 5.15 is only an LTS release for commercial license holders, Sigil will not be moving away from Qt-5.12.x until we are literally forced to. Qt's recent policy changes simply stink. I am waiting for some decent organization to fork Qt 5.12 or 5.15 and keep fixing the many many bugs.

Perhaps DiapDealer has an idea?

[DiapDealer]

We can still build 5.15 from source with the open-source license, right? It was my understanding that only the precompiled binary installers were reserved for commercial users.

It was always my plan to eventually move to Qt 5.15 LTS, since we build Qt from source anyway for Windows and Mac (much like Arch is doing already) as long as it works OK. But perhaps I'm missing something about why we should stay away from building/using the latest LTS source ourselves?

I've not updated my Arch system to Qt5.15 yet. I'll have to do some testing before I can determine what might have gone wrong with it and Sigil. It's possible the Sigil package on Arch might need to be rebuilt for Qt5.15. It had to be rebuilt for Python 3.8, for instance. If so, I'm sure they'll do it soon. In the meantime, I should be able to manually rebuild Sigil with the updated system Qt this weekend.

[DiapDealer]

My God, what did they do?! Something is badly, badly wrong, here. Sigil's absolutely unusable on Arch with the system provided Qt 5.15.0.

Why are people so dead-set on breaking things?

[DiapDealer]

Just completely fubar-ed. I'm a bit of loss here, actually.

[DiapDealer]

OK. What I know:

1) My hardcoded darkmode for Linux (enabled by environment variable) is totally borked. Only the dockwidgets (with the exception of Preview) are dark. Annoying, but not crucial at the moment. System qt dark themes seem to work.

2) QtWebEngine won't display images. This affects both Preview and Image tabs.

3) QtWebEngine is ignoring (or not finding) css. It uses the qrc-included darkmode css where appropriate, but nothing from book-supplied css or custom user preview css is being applied to any any page elements. Though inspector shows the css linked, only the default user-agent css and the qrc-supplied darkmode css are being applied to any page elements.

[DiapDealer]

I think it's some sort of "heightened security" RE loading local resources.

[DiapDealer]

Wow! It's down to line 4292 in MainWindow.cpp.

web_settings->setAttribute(QWebEngineSettings::LocalContentCanAccessFileUrls, false;

Changing that to true allows things (images, css, etc) to work again. But if that's the case, I'm not certain how loading local file url resources was ever working in Sigil. That setting has been set to false since the first official version with QtWebEngine!

Perhaps they've finally gotten around to honoring the setting in Qt5.15, where earlier versions of Qt didn't?

@KevinH: Are there specific reasons why we've set that to false? The description of the attribute seems fairly self explanatory. And by my reckoning, we've always needed local content to be able to load local file urls in Sigil, right?

Now if I can just figure out why my hardcoded dark theme got borked by 5.15.0

[KevinH]

That setting used to be for javascript to access local file urls, not xhtml src urls.
Perhaps someone changed its meaning, or Qt has moved to javascript to find and load all urls in the xhtml file.

Go ahead and change it in master if you get a moment. PageEdit may need the same fix.

Qt has announced that Qt 5.15 will NOT be an LTS release for open source projects. It will just get 1 or 2 minor revisions. No additional bug fixes for Qt 5.15 will be released after that. LTS fixes and support will not be released until 12 months later!


As result, I will no longer be filing bug reports or fixes for Qt as I am not getting paid to fix the bugs of others and get none of them back.

I am hoping for a nice Qt fork by someone to stop this nonsense.

They also dropped support for macOS 10.12 for no valid reason when they went to Qt 5.15.

This Qt race to produce more and more buggy software is for the birds.

[DiapDealer]

Do I need to ifdef the change at all for any reason? I can restrict it to >= Qt5.15.0 if that would be safer than just changing it wholesale.

Understood about the rest (and agreed). No need to move to 5.15 for our Mac/Windows installers in that case. I just need to make sure it will still run on Linux distros that DO package 5.15.x.