diff --git a/spyder/config/utils.py b/spyder/config/utils.py
index 86fa5ebbea1..590aec60906 100644
--- a/spyder/config/utils.py
+++ b/spyder/config/utils.py
@@ -116,9 +116,20 @@ def get_filter(filetypes, ext):
 
 def get_edit_filetypes():
     """Get all file types supported by the Editor"""
-    pygments_exts = _get_pygments_extensions()
-    favorite_exts = ['.py', '.R', '.jl', '.ipynb', '.md', '.pyw', '.pyx', '.C', '.CPP']
-    other_exts = [ext for ext in pygments_exts if ext not in favorite_exts]
+    # The filter details are not hidden on Windows, so we can't use
+    # all Pygments extensions on that platform
+    if os.name == 'nt':
+        supported_exts = []
+    else:
+        supported_exts = _get_pygments_extensions()
+
+    # NOTE: Try to not add too much extensions to this list to not
+    # make the filter look too big on Windows
+    favorite_exts = ['.py', '.R', '.jl', '.ipynb', '.md', '.pyw', '.pyx',
+                     '.c', '.cpp', '.json', '.dat', '.csv', '.tsv', '.txt',
+                     '.ini', '.html', '.js', '.h', '.bat']
+
+    other_exts = [ext for ext in supported_exts if ext not in favorite_exts]
     all_exts = tuple(favorite_exts + other_exts)
     text_filetypes = (_("Supported text files"), all_exts)
     return [text_filetypes] + EDIT_FILETYPES
@@ -171,3 +182,26 @@ def is_gtk_desktop():
             return False
     else:
         return False
+
+
+def is_kde_desktop():
+    "Detect if we are running in a KDE desktop"
+    if sys.platform.startswith('linux'):
+        xdg_desktop = os.environ.get('XDG_CURRENT_DESKTOP', '')
+        if xdg_desktop:
+            if 'KDE' in xdg_desktop:
+                return True
+            else:
+                return False
+        else:
+            return False
+    else:
+        return False
+
+
+def is_anaconda():
+    "Detect if we are running under Anaconda."
+    for var in os.environ:
+        if var.startswith('CONDA'):
+            return True
+    return False
diff --git a/spyder/widgets/editor.py b/spyder/widgets/editor.py
index 29974a5ce48..1b764e44343 100644
--- a/spyder/widgets/editor.py
+++ b/spyder/widgets/editor.py
@@ -24,15 +24,15 @@
 from qtpy.QtCore import (QByteArray, QFileInfo, QObject, QPoint, QSize, Qt,
                          QThread, QTimer, Signal, Slot)
 from qtpy.QtGui import QFont
-from qtpy.QtWidgets import (QAction, QApplication, QHBoxLayout, QMainWindow,
-                            QMessageBox, QMenu, QSplitter, QVBoxLayout,
-                            QWidget, QListWidget, QListWidgetItem)
+from qtpy.QtWidgets import (QAction, QApplication, QFileDialog, QHBoxLayout,
+                            QMainWindow, QMessageBox, QMenu, QSplitter,
+                            QVBoxLayout, QWidget, QListWidget, QListWidgetItem)
 
 # Local imports
 from spyder.config.base import _, DEBUG, STDERR, STDOUT
 from spyder.config.gui import config_shortcut, get_shortcut
 from spyder.config.utils import (get_edit_filetypes, get_edit_filters,
-                                 get_filter)
+                                 get_filter, is_kde_desktop, is_anaconda)
 from spyder.py3compat import qbytearray_to_str, to_text_string
 from spyder.utils import icon_manager as ima
 from spyder.utils import (codeanalysis, encoding, sourcecode,
@@ -593,6 +593,10 @@ def __init__(self, parent, actions):
         # Reference to save msgbox and avoid memory to be freed.
         self.msgbox = None
 
+        # File types and filters used by the Save As dialog
+        self.edit_filetypes = None
+        self.edit_filters = None
+
     @Slot()
     def show_in_external_file_explorer(self, fnames=None):
         """Show file in external file explorer"""
@@ -1561,12 +1565,29 @@ def file_saved_in_other_editorstack(self, index, filename):
         finfo.lastmodified = QFileInfo(finfo.filename).lastModified()
 
     def select_savename(self, original_filename):
+        """Select a name to save a file."""
+        if self.edit_filetypes is None:
+            self.edit_filetypes = get_edit_filetypes()
+        if self.edit_filters is None:
+            self.edit_filters = get_edit_filters()
+
+        # Don't use filters on KDE to not make the dialog incredible
+        # slow
+        # Fixes issue 4156
+        if is_kde_desktop() and not is_anaconda():
+            filters = ''
+            selectedfilter = ''
+        else:
+            filters = self.edit_filters
+            selectedfilter = get_filter(self.edit_filetypes,
+                                        osp.splitext(original_filename)[1])
+
         self.redirect_stdio.emit(False)
         filename, _selfilter = getsavefilename(self, _("Save file"),
-                                       original_filename,
-                                       get_edit_filters(),
-                                       get_filter(get_edit_filetypes(),
-                                           osp.splitext(original_filename)[1]))
+                                    original_filename,
+                                    filters=filters,
+                                    selectedfilter=selectedfilter,
+                                    options=QFileDialog.HideNameFilterDetails)
         self.redirect_stdio.emit(True)
         if filename:
             return osp.normpath(filename)