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a/src/qtgui/preview.ui b/src/qtgui/preview.ui
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                        <widget class="QPushButton">
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                        <widget class="QPushButton">
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                            <property name="name">
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                            <property name="name">
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                                <cstring>nextButton</cstring>
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                                <cstring>nextButton</cstring>
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                            </property>
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                            </property>
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                            <property name="enabled">
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                            <property name="enabled">
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                                <bool>false</bool>
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                                <bool>true</bool>
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                            </property>
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                            </property>
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                            <property name="text">
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                            <property name="text">
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                                <string>&amp;Next</string>
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                                <string>&amp;Next</string>
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                            </property>
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                            </property>
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                            <property name="accel">
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                            <property name="accel">
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                        <widget class="QPushButton">
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                        <widget class="QPushButton">
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                            <property name="name">
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                            <property name="name">
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                                <cstring>prevButton</cstring>
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                                <cstring>prevButton</cstring>
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                            </property>
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                            </property>
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                            <property name="enabled">
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                            <property name="enabled">
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                                <bool>false</bool>
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                                <bool>true</bool>
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                            </property>
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                            </property>
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                            <property name="text">
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                            <property name="text">
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                                <string>&amp;Previous</string>
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                                <string>&amp;Previous</string>
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                            </property>
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                            </property>
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                            <property name="accel">
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                            <property name="accel">