diff --git a/extensions/fablabchemnitz/epilog_dashboard_bbox_adjust/epilog_dashboard_bbox_adjust.py b/extensions/fablabchemnitz/epilog_dashboard_bbox_adjust/epilog_dashboard_bbox_adjust.py
index c834bf21..0f70f858 100644
--- a/extensions/fablabchemnitz/epilog_dashboard_bbox_adjust/epilog_dashboard_bbox_adjust.py
+++ b/extensions/fablabchemnitz/epilog_dashboard_bbox_adjust/epilog_dashboard_bbox_adjust.py
@@ -59,7 +59,7 @@ class EpilogDashboardBboxAdjust(inkex.EffectExtension):
         else:
             #for element in self.svg.root.getchildren():
             for element in self.document.getroot().iter("*"):
-                if isinstance (element, inkex.ShapeElement):
+                if isinstance (element, inkex.ShapeElement) and element.tag != inkex.addNS('use','svg') and element.get('inkscape:groupmode') != 'layer': #bbox fails for svg:use elements and layers:
                     bbox += element.bounding_box()
 
         if abs(bbox.width) == math.inf or abs(bbox.height) == math.inf:
diff --git a/extensions/fablabchemnitz/laser_check/laser_check.inx b/extensions/fablabchemnitz/laser_check/laser_check.inx
new file mode 100644
index 00000000..f5ffadff
--- /dev/null
+++ b/extensions/fablabchemnitz/laser_check/laser_check.inx
@@ -0,0 +1,17 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<inkscape-extension xmlns="http://www.inkscape.org/namespace/inkscape/extension">
+    <name>Laser Check</name>
+    <id>fablabchemnitz.de.laser_check</id>
+    <!--<param name="depth" type="int" gui-text="Max nested group depth">1</param>-->
+    <effect>
+        <object-type>all</object-type>
+        <effects-menu>
+            <submenu name="FabLab Chemnitz">
+				<submenu name="Nesting/Cut Optimization"/>
+			</submenu>
+        </effects-menu>
+    </effect>
+    <script>
+        <command location="inx" interpreter="python">laser_check.py</command>
+    </script>
+</inkscape-extension>
\ No newline at end of file
diff --git a/extensions/fablabchemnitz/laser_check/laser_check.py b/extensions/fablabchemnitz/laser_check/laser_check.py
new file mode 100644
index 00000000..c509f36c
--- /dev/null
+++ b/extensions/fablabchemnitz/laser_check/laser_check.py
@@ -0,0 +1,327 @@
+#!/usr/bin/env python3
+
+import inkex
+from inkex.bezier import csplength, csparea
+from lxml import etree
+import re
+import math
+
+class LaserCheck(inkex.EffectExtension):
+    
+    '''
+    check for old styles which should be upgraded
+    border around complete content
+    '''
+    
+    #def add_arguments(self, pars):
+    #    pars.add_argument('-d', '--depth', type = int, default = 1, help = 'Convert nested group up to DEPTH layers deep')
+
+    def effect(self):
+        
+        def parseChildren(element):
+            if element not in selected:
+                selected.append(element)
+            children = element.getchildren()
+            if children is not None:
+                for child in children:
+                    if child not in selected:
+                        selected.append(child)
+                    parseChildren(child) #go deeper and deeper       
+        
+        #check if we have selected elements or if we should parse the whole document instead
+        selected = [] #total list of elements to parse
+        if len(self.svg.selected) == 0:
+            for element in self.document.getroot().iter(tag=etree.Element):
+                if element != self.document.getroot():
+
+                    selected.append(element)
+        else:
+            for element in self.svg.selected.values():
+                parseChildren(element)
+              
+              
+        namedView = self.document.getroot().find(inkex.addNS('namedview', 'sodipodi'))
+        doc_units = namedView.get(inkex.addNS('document-units', 'inkscape'))            
+        pagecolor = namedView.get('pagecolor')            
+        inkex.utils.debug("Document units: {}".format(doc_units))
+        
+        inkex.utils.debug("---------- Groups and layers") 
+        groups = []
+        layers = []
+        for element in selected:
+            if element.tag == inkex.addNS('g','svg'):
+                if element.get('inkscape:groupmode') == 'layer':
+                    layers.append(element)
+                else:
+                    groups.append(element)
+        inkex.utils.debug("{} groups in total".format(len(groups)))
+        inkex.utils.debug("{} layers in total".format(len(layers)))
+
+        #check for empty groups
+        for group in groups:
+            if len(group) == 0:
+                inkex.utils.debug("group id={} is empty".format(group.get('id')))
+
+        #check for empty layers
+        for layer in layers:
+            if len(layer) == 0:
+                inkex.utils.debug("layer id={} is empty".format(layer.get('id')))
+
+        inkex.utils.debug("---------- Clones (svg:use) - maybe unlink") 
+        uses = []
+        for element in selected:
+            if element.tag == inkex.addNS('use','svg'):
+                uses.append(element)
+        inkex.utils.debug("{} svg:use clones in total".format(len(uses)))
+        for use in uses:
+            inkex.utils.debug("clone id={}".format(use.get('id')))
+   
+        inkex.utils.debug("---------- Clippings (svg:clipPath) - please replace with real cut paths") 
+        clipPaths = []
+        for element in selected:
+            if element.tag == inkex.addNS('clipPath','svg'):
+                clipPaths.append(element)
+        inkex.utils.debug("{} svg:clipPath in total".format(len(clipPaths)))
+        for clipPath in clipPaths:
+            inkex.utils.debug("clipPath id={}".format(clipPath.get('id')))
+   
+   
+        inkex.utils.debug("---------- Images (svg:image) - maybe trace to svg") 
+        images = []
+        for element in selected:
+            if element.tag == inkex.addNS('image','svg'):
+                images.append(element)
+        inkex.utils.debug("{} svg:image in total".format(len(images)))
+        for image in images:
+            inkex.utils.debug("image id={}".format(image.get('id')))
+    
+        inkex.utils.debug("---------- Low level strokes (svg:line/polyline/polygon) - maybe convert to path") 
+        lowlevels = []
+        for element in selected:
+            if element.tag in (inkex.addNS('line','svg'), inkex.addNS('polyline','svg'), inkex.addNS('polygon','svg')):
+                lowlevels.append(element)
+        inkex.utils.debug("{} low level strokes in total".format(len(lowlevels)))
+        for lowlevel in lowlevels:
+            inkex.utils.debug("stroke id={}".format(lowlevel.get('id')))
+    
+        inkex.utils.debug("---------- Texts (should be converted to paths)") 
+        texts = []
+        for element in selected:
+            if element.tag == inkex.addNS('text','svg'):
+                texts.append(element)
+        inkex.utils.debug("{} svg:text in total".format(len(texts)))
+        for text in texts:
+            inkex.utils.debug("text id={}".format(text.get('id')))
+             
+                
+        inkex.utils.debug("---------- Shapes / Non-shapes")        
+        nonShapes = []
+        shapes = []
+        for element in selected:       
+            if not isinstance(element, inkex.ShapeElement):
+                nonShapes.append(element)
+            else:
+                shapes.append(element)  
+        inkex.utils.debug("{} shape elements in total".format(len(shapes)))
+        inkex.utils.debug("{} non-shape elements in total".format(len(nonShapes)))
+        for nonShape in nonShapes:
+            inkex.utils.debug("non-shape id={}".format(nonShape.get('id')))
+
+        inkex.utils.debug("---------- Stroke colors")
+        strokeColors = []
+        for element in shapes:          
+            style = element.get('style')
+            if style is not None:
+                stroke = re.search('(;|^)stroke:(.*?)(;|$)', style)
+                if stroke is not None:
+                    strokeColor = stroke[0].split("stroke:")[1].split(";")[0]
+                    if strokeColor not in strokeColors:
+                        strokeColors.append(strokeColor)
+        inkex.utils.debug("{} different stroke colors in total".format(len(strokeColors)))
+        for strokeColor in strokeColors:
+            inkex.utils.debug("stroke color {}".format(strokeColor))
+              
+        inkex.utils.debug("---------- Borders around all elements - minimum offset 5mm from each side")
+        bbox = inkex.BoundingBox()
+        for element in self.document.getroot().iter(tag=etree.Element):
+            if element != self.document.getroot() and isinstance(element, inkex.ShapeElement) and element.tag != inkex.addNS('use','svg') and element.get('inkscape:groupmode') != 'layer': #bbox fails for svg:use elements and layers
+                transform = inkex.Transform()
+                parent = element.getparent()
+                if parent is not None and isinstance(parent, inkex.ShapeElement):
+                    transform = parent.composed_transform()
+                try:
+                    bbox += element.bounding_box(transform)
+                except Exception:
+                    transform = element.composed_transform()
+                    x1, y1 = transform.apply_to_point([0, 0])
+                    x2, y2 = transform.apply_to_point([1, 1])
+                    bbox += inkex.BoundingBox((x1, x2), (y1, y2))
+ 
+        if abs(bbox.width) == math.inf or abs(bbox.height) == math.inf:
+            inkex.utils.debug("bounding box could not be calculated")
+        else:
+            inkex.utils.debug("bounding box is {}".format(bbox))
+        page_width = self.svg.unittouu(self.document.getroot().attrib['width'])
+        width_height = self.svg.unittouu(self.document.getroot().attrib['height'])
+        fmm = self.svg.unittouu("5mm")
+        if bbox.left > fmm:
+            self.msg("left ok")
+        else:
+            self.msg("left fail")
+             
+        if bbox.top > fmm:
+            self.msg("top ok")
+        else:
+            self.msg("top fail")
+            
+        if bbox.right + fmm <= page_width:
+            self.msg("right ok")
+        else:
+            self.msg("right fail")
+            
+        if bbox.bottom + fmm <= width_height:
+            self.msg("bottom ok")
+        else:
+            self.msg("bottom fail")
+                           
+        inkex.utils.debug("---------- Stroke widths")
+        strokeWidths = []
+        for element in shapes:          
+            style = element.get('style')
+            if style is not None:
+                stroke_width = re.search('stroke-width:(.*?)(;|$)', style)
+                if stroke_width is not None:
+                    strokeWidth = self.svg.unittouu(stroke_width[0].split("stroke-width:")[1].split(";")[0])
+                    if strokeWidth not in strokeWidths:
+                        strokeWidths.append(strokeWidth)
+        inkex.utils.debug("{} different stroke widths in total".format(len(strokeWidths)))
+        for strokeWidth in strokeWidths:
+            inkex.utils.debug("stroke width {}".format(strokeWidth))
+          
+        inkex.utils.debug("---------- Cosmetic dashes - should be converted to paths")
+        strokeDasharrays = []
+        for element in shapes:          
+            style = element.get('style')
+            if style is not None:
+                stroke_dasharray = re.search('stroke-dasharray:(.*?)(;|$)', style)
+                if stroke_dasharray is not None:
+                    strokeDasharray = stroke_dasharray[0].split("stroke-dasharray:")[1].split(";")[0]
+                    if strokeDasharray not in strokeDasharrays:
+                        strokeDasharrays.append(strokeDasharray)
+        inkex.utils.debug("{} different stroke dash arrays in total".format(len(strokeDasharrays)))
+        for strokeDasharray in strokeDasharrays:
+            inkex.utils.debug("stroke dash array {}".format(strokeDasharray))
+                
+        inkex.utils.debug("---------- Invisible shapes")
+        invisibles = []
+        for element in shapes:
+            if element.tag not in (inkex.addNS('tspan','svg')):      
+                style = element.get('style')
+                if style is not None:              
+                    stroke = re.search('stroke:(.*?)(;|$)', style) #filter white on white (we guess the background color of the document is white too but we do not check)
+                    if stroke is None:
+                        strokeVis = 0
+                    elif stroke[0].split("stroke:")[1].split(";")[0] == 'none':
+                        strokeVis = 0
+                    elif stroke[0].split("stroke:")[1].split(";")[0] in ('#ffffff', 'white', 'rgb(255,255,255)'):
+                        strokeVis = 0
+                    else:
+                        strokeVis = 1
+                    
+                    stroke_width = re.search('stroke-width:(.*?)(;|$)', style)
+                    if stroke_width is None:
+                        widthVis = 0
+                    elif self.svg.unittouu(stroke_width[0].split("stroke-width:")[1].split(";")[0]) < 0.005: #really thin (0,005pc = 0,080px)
+                        widthVis = 0
+                    else:
+                        widthVis = 1
+  
+                    stroke_opacity = re.search('stroke-opacity:(.*?)(;|$)', style)
+                    if stroke_opacity is None:
+                        strokeOpacityVis = 0
+                    elif float(stroke_opacity[0].split("stroke-opacity:")[1].split(";")[0]) < 0.05: #nearly invisible (<5% opacity)
+                        strokeOpacityVis = 0
+                    else:
+                        strokeOpacityVis = 1
+  
+                    if pagecolor == '#ffffff':
+                        invisColors = [pagecolor, 'white', 'rgb(255,255,255)']
+                    else:
+                        invisColors = [pagecolor] #we could add some parser to convert pagecolor to rgb/hsl/cmyk
+                    fill = re.search('fill:(.*?)(;|$)', style)
+                    if fill is None:
+                        fillVis = 0
+                    elif fill[0].split("fill:")[1].split(";")[0] == 'none':
+                        fillVis = 0
+                    elif fill[0].split("fill:")[1].split(";")[0] in invisColors:
+                        fillVis = 0
+                    else:
+                        fillVis = 1
+              
+                    fill_opacity = re.search('fill-opacity:(.*?)(;|$)', style)
+                    if fill_opacity is None:
+                        fillOpacityVis = 0
+                    elif float(fill_opacity[0].split("fill-opacity:")[1].split(";")[0]) < 0.05: #nearly invisible (<5% opacity)
+                        fillOpacityVis = 0
+                    else:
+                        fillOpacityVis = 1  
+                              
+                    #self.msg("strokeVis={}, widthVis={}, strokeOpacityVis={}, fillVis={}, fillOpacityVis={}".format(strokeVis, widthVis, strokeOpacityVis, fillVis, fillOpacityVis))
+                    if (strokeVis == 0 or widthVis == 0 or strokeOpacityVis == 0) and (fillVis == 0 or fillOpacityVis == 0):
+                        if element not in invisibles:
+                            invisibles.append(element)
+        inkex.utils.debug("{} invisible shapes in total".format(len(invisibles)))
+        for invisible in invisibles:
+            inkex.utils.debug("shape id={}".format(invisible.get('id')))
+                    
+        inkex.utils.debug("---------- Objects with stroke transparencies (< 1.0) - should be set to 1.0")
+        transparencies = []
+        for element in shapes:
+              style = element.get('style')
+              if style is not None:              
+                  stroke_opacity = re.search('stroke-opacity:(.*?)(;|$)', style)
+                  if stroke_opacity is not None:
+                      if float(stroke_opacity[0].split("stroke-opacity:")[1].split(";")[0]) < 1.0:
+                          if element not in transparencies:
+                              transparencies.append(element)
+        inkex.utils.debug("{} stroke transparencies shapes in total".format(len(transparencies)))
+        for transparency in transparencies:
+            inkex.utils.debug("shape id={}".format(transparency.get('id')))  
+              
+        inkex.utils.debug("---------- Pointy paths - should be deleted")
+        pointyPaths = []
+        for element in shapes:
+            if isinstance(element, inkex.PathElement):
+                p = element.path
+                commandsCoords = p.to_arrays()
+                if len(commandsCoords) == 1 or \
+                    (len(commandsCoords) == 2 and commandsCoords[0][1] == commandsCoords[1][1]) or \
+                    (len(commandsCoords) == 2 and commandsCoords[-1][0] == 'Z') or \
+                    (len(commandsCoords) == 3 and commandsCoords[0][1] == commandsCoords[1][1] and commandsCoords[2][1] == 'Z'):
+                    pointyPaths.append(element)
+        inkex.utils.debug("{} pointy paths in total".format(len(pointyPaths)))
+        for pointyPath in pointyPaths:
+            inkex.utils.debug("path id={}".format(pointyPath.get('id')))    
+   
+        inkex.utils.debug("---------- Transformations - should be applied to absolute")
+        transformations = []
+        for element in shapes:
+            if element.get('transform') is not None:
+                transformations.append(element)
+        inkex.utils.debug("{} transformation in total".format(len(transformations)))
+        for transformation in transformations:
+            inkex.utils.debug("transformation in id={}".format(transformation.get('id')))    
+              
+        inkex.utils.debug("---------- Short paths (< 1mm)")
+        shortPaths = []
+        for element in shapes:
+            if isinstance(element, inkex.PathElement):
+                slengths, stotal = csplength(element.path.transform(element.composed_transform()).to_superpath())
+                if stotal < self.svg.unittouu("1mm"):
+                    shortPaths.append(element)
+        inkex.utils.debug("{} short paths in total".format(len(shortPaths)))
+        for shortPath in shortPaths:
+            inkex.utils.debug("short path id={}".format(shortPath.get('id')))    
+                             
+if __name__ == '__main__':
+    LaserCheck().run()
\ No newline at end of file
diff --git a/extensions/fablabchemnitz/laser_check/meta.json b/extensions/fablabchemnitz/laser_check/meta.json
new file mode 100644
index 00000000..c4a26db5
--- /dev/null
+++ b/extensions/fablabchemnitz/laser_check/meta.json
@@ -0,0 +1,19 @@
+[
+  {
+    "name": "Laser Check",
+    "id": "fablabchemnitz.de.laser_check",
+    "path": "laser_check",
+    "original_name": "Laser Checkr",
+    "original_id": "fablabchemnitz.de.laser_check",
+    "license": "GNU GPL v4",
+    "license_url": "",
+    "comment": "",
+    "source_url": "https://gitea.fablabchemnitz.de/FabLab_Chemnitz/mightyscape-1.X/src/branch/master/extensions/fablabchemnitz/laser_check",
+    "fork_url": null,
+    "documentation_url": "",
+    "inkscape_gallery_url": null,
+    "main_authors": [
+      "github.com/vmario89"
+    ]
+  }
+]
\ No newline at end of file
diff --git a/extensions/fablabchemnitz/optimize_sequence_lasercut_sequence/meta.json b/extensions/fablabchemnitz/optimize_sequence_lasercut_sequence/meta.json
index f0a90c91..ab2babba 100644
--- a/extensions/fablabchemnitz/optimize_sequence_lasercut_sequence/meta.json
+++ b/extensions/fablabchemnitz/optimize_sequence_lasercut_sequence/meta.json
@@ -5,7 +5,7 @@
     "path": "optimize_sequence_lasercut_sequence",
     "original_name": "Fix cutting sequence",
     "original_id": "L0laapk3.filter.lasercut_sequence",
-    "license": "CC BY-NC-SA 4.0",
+    "license": "GNU AGPL v3",
     "license_url": "https://github.com/L0laapk3/inkscape-laser-sequence-extension/blob/master/LICENSE",
     "comment": "ported to Inkscape v1 by Mario Voigt",
     "source_url": "https://gitea.fablabchemnitz.de/FabLab_Chemnitz/mightyscape-1.X/src/branch/master/extensions/fablabchemnitz/optimize_sequence_lasercut_sequence",
diff --git a/extensions/fablabchemnitz/ungrouper_and_element_migrator_filter/ungrouper_and_element_migrator_filter.inx b/extensions/fablabchemnitz/ungrouper_and_element_migrator_filter/ungrouper_and_element_migrator_filter.inx
index 258f994c..2d4668a7 100644
--- a/extensions/fablabchemnitz/ungrouper_and_element_migrator_filter/ungrouper_and_element_migrator_filter.inx
+++ b/extensions/fablabchemnitz/ungrouper_and_element_migrator_filter/ungrouper_and_element_migrator_filter.inx
@@ -43,7 +43,8 @@
         					<!--<param name="svg" type="bool" gui-text="svg">true</param>-->
         					<!--<param name="sodipodi" type="bool" gui-text="sodipodi">true</param>-->
         					<param name="clipPath" type="bool" gui-text="clipPath">true</param>
-        					<param name="defs" type="bool" gui-text="defs">true</param>
+                            <param name="defs" type="bool" gui-text="defs">true</param>
+                            <param name="desc" type="bool" gui-text="desc">true</param>
         					<param name="image" type="bool" gui-text="image">true</param>
                             <param name="guide" type="bool" gui-text="guide">true</param>
         					<param name="mask" type="bool" gui-text="mask">true</param>
diff --git a/extensions/fablabchemnitz/ungrouper_and_element_migrator_filter/ungrouper_and_element_migrator_filter.py b/extensions/fablabchemnitz/ungrouper_and_element_migrator_filter/ungrouper_and_element_migrator_filter.py
index 1af9dce8..741aeaf8 100644
--- a/extensions/fablabchemnitz/ungrouper_and_element_migrator_filter/ungrouper_and_element_migrator_filter.py
+++ b/extensions/fablabchemnitz/ungrouper_and_element_migrator_filter/ungrouper_and_element_migrator_filter.py
@@ -41,6 +41,7 @@ class UngrouperAndElementMigratorFilter(inkex.EffectExtension):
         pars.add_argument("--circle",         type=inkex.Boolean, default=True)
         pars.add_argument("--clipPath",       type=inkex.Boolean, default=True)
         pars.add_argument("--defs",           type=inkex.Boolean, default=True)
+        pars.add_argument("--desc",           type=inkex.Boolean, default=True)
         pars.add_argument("--ellipse",        type=inkex.Boolean, default=True)
         pars.add_argument("--image",          type=inkex.Boolean, default=True)
         pars.add_argument("--guide",          type=inkex.Boolean, default=True)
@@ -77,6 +78,7 @@ class UngrouperAndElementMigratorFilter(inkex.EffectExtension):
         namespace.append("{http://www.w3.org/2000/svg}circle")                        if self.options.circle         else ""
         namespace.append("{http://www.w3.org/2000/svg}clipPath")                      if self.options.clipPath       else ""
         namespace.append("{http://www.w3.org/2000/svg}defs")                          if self.options.defs           else ""     
+        namespace.append("{http://www.w3.org/2000/svg}desc")                          if self.options.desc           else ""     
         namespace.append("{http://www.w3.org/2000/svg}ellipse")                       if self.options.ellipse        else ""
         namespace.append("{http://www.w3.org/2000/svg}image")                         if self.options.image          else ""
         namespace.append("{http://www.w3.org/2000/svg}line")                          if self.options.line           else ""