Compile error on ubuntu 20.04 using QLatin1String::arg()

[pieper]

Summary

Using the standard linux build instructions on ubuntu 20.04 (in a github codespace) these lines generate an error due to missing .arg method:

Slicer/Base/QTGUI/qSlicerExtensionsLocalWidget.cxx

Lines 419 to 435 in 6639f29

	// Status line
	QString statusText;
	if (!available && missing) // "missing" is checked so that we don't display this message when there have been no update checks before
	{
	statusText += QString("<p style=\"font-weight: bold; font-size: 80%; color: %1;\">"
	"<img style=\"float: left\" src=\":/Icons/ExtensionIncompatible.svg\"/> ").arg(this->WarningColor) +
	qSlicerExtensionsLocalWidget::tr("Not found for this version of the application (r%1)")
	.arg(this->SlicerRevision) + QLatin1String("</p>");
	}
	if (!compatible)
	{
	statusText += QLatin1String("<p style=\"font-weight: bold; font-size: 80%; color: %1;\">"
	"<img style=\"float: left\" src=\":/Icons/ExtensionIncompatible.svg\"/> ").arg(this->WarningColor) +
	qSlicerExtensionsLocalWidget::tr("Incompatible with Slicer r%1 [built for r%2]")
	.arg(this->SlicerRevision)
	.arg(this->WidgetItem->data(qSlicerExtensionsLocalWidgetPrivate::InstalledExtensionSlicerVersionRole).toString()) + QLatin1String("</p>");
	}

Commenting out the lines allows the compilation to complete and Slicer runs.

Steps to reproduce

Follow linux build instructions.

Environment

Slicer main as of 6639f29, build on Ubuntu 20.04.6 LTS

See also

commontk/CTK#1196

[Punzo]

For reference: commontk/CTK#1196 (comment)